polaradj.n.

Brit.

/ˈpəʊlə/, U.S.

/ˈpoʊlər/

Forms: 1500s pollard, 1500s– polar.

Origin: Of multiple origins. Partly a borrowing from Latin. Partly formed within English, by derivation. Etymons: Latin polaris ; pole n.², -ar suffix¹.

Etymology: Partly < post-classical Latin polaris of the sky or heaven (from 8th cent. in British sources), of or relating to the North or South Pole or pole star (a1275 in a British source; < classical Latin polus pole n.² + -āris -ar suffix¹), and partly (in later use) < pole n.² + -ar suffix¹. Compare Middle French, French polaire (1432 or earlier), Spanish polar (1507 or earlier), Italian polare (1573), all earliest in sense A. 1a.In sense B. 2 after French polaire du point (J. D. Gergonne 1812, in Ann. des math. 3 297). With polar body n. compare French globule polaire (1875 or earlier; usually in plural). With polar circle n. compare Middle French, French cercle polaire (1432 or earlier). In polar coordinate n. probably after French coordonnée polaire (1811 or earlier; usually in plural). With polar vector n. compare French vecteur polaire (1901 or earlier).

A. adj.

a. Of or relating to the North or South Pole of the earth (or another celestial object), or the poles of the celestial sphere; situated near or aligned with respect to a pole; characteristic of or occurring in the regions near a pole. Cf. pole n.² 1.Recorded earliest in polar circle n. at Compounds.

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the world > the universe > celestial sphere > [adjective] > pole

polar1556

polary1559

the world > the earth > geodetic references > [adjective] > pole

polar1556

polary1559

subpolar1685

circumpolar1696

polifugal1744

poleward1848

bipolar1896

1556 R. Record Castle of Knowl. 41 Recken from one of the poles..23 degrees and an halfe,..draw a circle of that circuit about eche Pole... These circles maye well bee called Pole circles, or Polar circles.

1595 J. Davis Seamans Secrets ii. sig. H4^v The Artick Polar Circle is one of the lesser circles, deuiding the sphere into two vnequall partes.

1667 J. Milton Paradise Lost x. 289 As when two Polar Winds..together drive Mountains of Ice.

a1711 T. Ken Hymnotheo iv, in Wks. (1721) III. 120 Devotion cold as Polar Ice was grown.

1786 A. Becket Trip to Holland 41 Do we not find in the Polar regions the same degree of barbarism that marks the inhabitants of the Torrid Zone?

1790 H. J. Pye Amusement 7 The lengthen'd horrors of a polar night, Where..No dawning light shall gild the mountain's brow.

1856 E. K. Kane Arctic Explor. I. xxiii. 302 Well known to the Polar traveller.

1878 T. H. Huxley Physiography (ed. 2) 178 The cold polar waters sink by their density.

1937 J. E. Tilden Algae & their Life Relations (ed. 2) 22 One must expect to find fewer green algae in the land of long, dark nights—the polar regions.

1968 Solar Physics 3 321 The appearance of the solar corona over the poles at time of low solar activity is dominated by the presence of polar plumes.

2001 Time 17 Dec. 16 The circling Arctic winds weaken and cold air descends from the polar region.

b. Analogous to the Pole Star or to the poles of the earth in serving to guide, direct, or impel others.

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society > authority > control > [adjective] > leading or guiding

conductive1528

directional1612

guidinga1616

leadinga1628

manuducent1677

conducting1710

bear-leading1748

bear-leading1766

polar1791

1791 T. Paine Rights of Man i. 117 When a man in a long cause attempts to steer his course by any thing else than some polar truth or principle, he is sure to be lost.

1801 Ann. Reg. 1799 (Otridge ed.) ii. App. to Chron. 156/1 Universal Emancipation, with Representative Legislature, was the polar principle which guided the Society of United Irishmen.

1858 T. Carlyle Hist. Friedrich II of Prussia I. i. i. 7 A king over men; whose movements were polar, and carried..those of the world along with them.

1899 Expositor Jan. 51 Both the Church and the world depend in crisis on the man of insight:..the polar primary man.

1927 V. L. Parrington Colonial Mind 152 To one cardinal principle Edwards was faithful—the conception of the majesty and sufficiency of God; and this polar idea provides the clue to both his philosophical and theological systems.

2000 B. Meeks Narr. Resistance 163 One needs also to probe the extent to which Cuba, Nicaragua, Grenada, and the rest of the Left that did not achieve state power, departed from some abstract, polar notion of authoritarianism.

c. Of clothing: designed to be worn in very cold weather such as prevails in polar regions. Cf. polar fleece n. at Compounds.

ΚΠ

1885 Messenger (Indiana, Pa.) 9 Dec. 3/6 Arctic Overshoes for men and women... Polar boots at $1,25 per pair.

1926 Geogr. Jrnl. 68 45 Articles, such as..polar clothing.

1978 Newport (Rhode Island) Daily News 13 Nov. 7/1 In the middle of a record cold snap, Charles receives an expensive polar suit from his parents.

2003 Weekend Austral. (Nexis) 27 Dec. b36 It was far too cold to lounge about in a Como turtleneck, so we got about in long johns and thermals and..polar jackets.

a. Originally: designating the property of some substances of aligning themselves in the direction of the earth's poles; magnetic. In later use also: of or relating to one of the poles of a magnet; having magnetic poles. Cf. pole n.² 6.

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the world > matter > physics > electromagnetic radiation > magnetism > magnetic devices or materials > [adjective] > polar

polar1613

polary1646

1613 M. Ridley Short Treat. Magneticall Bodies 62 The iron barres..being..placed North and South, do receive a polar vertue, and directory faculty.

1692 T. P. Blount Ess. 88 The Polar Vertue of the Loadstone was unknown to the Ancients.

1705 E. Scarburgh Eng. Euclide 2 In Loadstones it is commonly known that there are Polar Points, called North and South.

1821 H. Davy in Philos. Trans. (Royal Soc.) 111 16 A body was moved round the circle from the north to the south poles of the same wire... It was perfectly evident..that as many polar arrangements may be formed as chords can be drawn in circles surrounding the wire.

1860 J. Tyndall Glaciers of Alps i. xx. 142 I examined the stones..and found them strongly polar.

1872 W. Thomson Reprint Papers 421 A polar magnet, as I shall henceforth call anything magnetized after the manner of a loadstone or a steel magnet.

1891 S. P. Thompson Electromagnet 39 The pole or polar region of a magnet is simply that part of the surface of a magnet whence the internal magnetic lines emerge into the air.

1925 H. C. Booth tr. F. Auerbach Mod. Magnetics (U.K. ed.) ii. 35 Small molecular magnets, each of which possesses a definite moment ml (the product of the polar strength and the polar distance).

2003 Times (Nexis) 28 May (Times2 section) 4 Fisk makes eye contact as though he is trying to force together the polar opposites of a magnet.

†b. Science. Designating an arrangement or orientation of particles in a particular direction (like iron filings under the influence of a magnet). Obsolete.

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the world > matter > chemistry > chemical structure or stereochemistry > [adjective] > of or relating to polarization

polar1776

1776 B. Higgins Philos. Ess. Light I. p. xxvii Estimations of the force of this attraction in contact, and at given distances, in fortuitous, and in polar arrangement of the atoms.

1850 W. R. Grove On Correlation Physical Forces (ed. 2) 36 At the point of maximum density the molecules of these bodies assume a polar or crystalline condition.

1870 H. Spencer Princ. Psychol. (ed. 2) I. v. ii. 517 Adjacent molecules will be unsymmetrically placed..they will not stand in polar order.

3. Mathematics. Relating to or referred to a pole (pole n.² 8); of the nature of a polar (sense B. 2).See also polar coordinate n. at Compounds, polar curve n., polar diagram n. at Compounds.Recorded earliest in polar equation n. at Compounds.

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the world > relative properties > number > geometry > point > [adjective]

umbilical1728

polar1813

umbilicar1843

connectant1863

stigmatic1863

cuspidal1874

tropal1875

cusped1879

copunctal1896

open1896

perfect1897

closed1902

1813 Philos. Trans. (Royal Soc.) 103 12 By the polar equation of the curve, SQ = ^p/ ₂. cosec.(^MSQ/ ₂)².

1879 W. Thomson & P. G. Tait Treat. Nat. Philos. (new ed.) I: Pt. i. §134 The polar figure to any continuous curve on a spherical surface is the locus of the ultimate intersections of great circles equatorial to points taken infinitely near each other along it.

1972 M. Kline Math. Thought xxxv. 845 One of Poncelet's objectives in studying polar reciprocation with respect to a conic was to establish the principle of duality.

1991 C. B. Boyer & U. C. Merzbach Hist. Math. (ed. 2) viii. 127 If point P on the spiral is chosen.., the polar subtangent OQ will be precisely equal to quarter of the circumference of the circle of radius OP.

a. Of or designating forces acting in opposing directions. Chiefly figurative.

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the world > space > direction > [adjective] > having opposite direction > of forces

polar1818

polaristic1859

polaric1863

1818 S. T. Coleridge Friend (new ed.) I. 155 There is, strictly speaking, no proper opposition but between the two polar forces of one and the same power.

1862 W. R. Grove On Correlation Physical Forces (ed. 4) 38 Cases where a dual or polar character of force is manifested.

1863 E. V. Neale Analogy Thought & Nature 45 The thought of centres of force becomes that of polar force, where the most entire union is produced by the most complete opposition.

1913 G. F. Moore Hist. Relig. I. iv. 71 The Chinese philosophy of nature, with its two polar forces, Yang and Yin.

1983 J. L. Sundquist Dynamics Party Syst. (rev. ed.) v. 79 The Republican leaders, who were a polar force on the one issue, acted as moderate centrists on the others.

1996 N.Y. Rev. Bks. 3 Oct. 24/1 The polar forces of deed and reflection that we find in the heroes of classical German drama.

b. Directly opposite in character, action, or tendency; representing an extreme case.

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the world > relative properties > relationship > contrariety or contrast > [adjective] > opposite or opposed

turneda1325

reversedc1390

contrary1413

opposeda1500

oppositea1513

inverted1563

counter1596

diametrical1613

contraposed1620

oppositive1622

averse1623

diagonial1624

contrarying1628

diametrala1631

conversive1636

Antipodian1640

converted1640

exadverse1647

Antarctic1651

Antipodean1651

antipodal1664

in reverse1694

contradictory1736

converse1794

antithesistic1801

contravening1802

diametric1802

reverse1828

polar1832

antipodist1844

antithetic1864

other-sided1879

antipodic1881

1832 Blackwood's Edinb. Mag. June 998 Rusticity and Urbanity are polar opposites.

1841 T. Carlyle On Heroes iii. 157 Dante felt Good and Evil to be the two polar elements of this Creation, on which it all turns.

1853 T. De Quincey Autobiogr. Sketches vii. 224 Talent and genius..are not merely different; they are in polar opposition to each other.

1935 H. Read Green Child 238 Order and Disorder might be taken as the polar opposites that together constituted a single harmonious whole.

1972 Sci. Amer. Jan. 35/1 Although sex-role ideologies form a continuum, we grouped the respondents into two polar categories, which we labeled ‘traditional’ and ‘contemporary’.

1988 Q. N. Myrvik & R. S. Weiser Fund. Med. Bacteriol. & Mycol. (ed. 2) xxvii. 401 Most cases of leprosy belong to one of two polar forms of the disease, lepromatous leprosy..and tuberculoid type leprosy.

1994 J. Edwards Multilingualism (1995) vii. 177 The very terms pluralism and assimilation seem not, after all, to be such polar opposites as might first be thought.

a. Physical Chemistry. (Of chemical decomposition) occurring at one or other pole in electrolysis; relating to the poles of a battery or cell. Cf. pole n.² 10. Now rare.

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the world > matter > physics > electromagnetic radiation > electricity > galvanism, voltaism > [adjective] > relating to poles

polar1826

the world > matter > physics > electromagnetic radiation > electricity > electric polarization > [adjective] > relating to poles

polar1826

1826 H. Davy in Philos. Trans. (Royal Soc.) 116 387 Conceiving that all decompositions might be polar, I electrised different compounds at the different extremities.

1833 M. Faraday in Philos. Trans. (Royal Soc.) 123 42 However distinct all these actions may be from true polar electro-chemical decompositions, they are still highly important, and well worthy of investigation.

1851 Abstr. Papers Royal Soc. 1843–50 5 501 The elements constituting the voltaic battery assume polar tension before the circuit is completed, even in a single cell.

1892 T. O'C. Sloane Standard Electr. Dict. (1893) 454 Polar region, in electro-therapeutics the area or region of the body near the therapeutic electrode.

1911 Physical Rev. 32 215 The optimum current depended on the polar distance and occurred at increasing current densities as the polar distance was increased.

b. Chemistry. Involving or relating to the separation of positive and negative electric charge between different parts of a molecule, atom, etc.; spec. (a) (of a chemical bond) ionic; (esp. of a solid) composed of ions; (b) (of a covalent bond) such that the electron charge density is unequally shared between the two atoms; (of a molecule or group) having an electric dipole moment; (esp. of a liquid) consisting of such molecules.

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the world > matter > chemistry > chemical bonding > [adjective] > of or relating to polar bonding

polar1882

1882 Amer. Naturalist 16 554 Each [molecule] must be composed of acid and basic, or positive and negative constituents, and thus be a chemically polar organism.

1913 Jrnl. Amer. Chem. Soc. 35 1443 In the preceding paragraphs we have suggested that there are two distinct types of union between atoms: polar, in which an electron has passed from one atom to the other, and non-polar, in which there is no motion of an electron.

1927 N. V. Sidgwick Electronic Theory of Valency iv. 52 Polar or ionizable linkages between the oppositely charged ions of a salt.

1936 S. Glasstone Recent Adv. Gen. Chem. vi. 257 Polar and non-polar liquids are generally immiscible.

1951 I. L. Finar Org. Chem. ii. 14 A symmetrical molecule is non-polar, although it may contain polar bonds.

1960 D. Nachmansohn in G. H. Bourne Struct. & Function Muscle II. v. 234 The carbonyl group has a marked polar character.

1974 J. S. Blakemore Solid State Physics (ed. 2) iv. 338 Optical phonon scattering..is especially important for a solid with a polar (partially or completely ionic) lattice.

1999 C. Mendelson Home Comforts xxviii. 383/2 Water is very highly polar. Polar substances remove stains caused by water-soluble substances.

6. Biology. Of or relating to the poles of a cell, organ, etc. Cf. pole cell n. at pole n.² Compounds. Now chiefly in polar body n. at Compounds.

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the world > life > biology > substance > cell > parts of cell > [adjective] > regions

polar1869

periplasmic1967

1869 Nature 30 Dec. 247/1 The ova when deposited never present the least trace of the polar-cell.

1888 G. Rolleston & W. H. Jackson Forms Animal Life (ed. 2) Introd. 22 A clear spot, the polar spot or corpuscle, may appear at each pole of the spindle.

1898 Arch. Surg. 9 356 Opacities in the vitreous and posterior polar cataract had made their appearance.

1988 Q. N. Myrvik & R. S. Weiser Fund. Med. Bacteriol. & Mycol. (ed. 2) ii. 37 Polar flagella exist either as a tuft of flagella (lophotrichous) or a single flagellum (monotrichous).

B. n.

†1. Astronomy. = polar circle n. at Compounds. Obsolete. rare.

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the world > the earth > geodetic references > [noun] > latitude > polar circle

Arctic Circlec1540

polar circle1556

Antarctic Circle1587

polar line1658

polar1688

1688 G. Sinclair Princ. Astron. & Navigation 33 The polars..are two in number, the polar artick, and the polar antartick.

2. Geometry. The straight line joining the two points at which tangents from a given point touch a conic section.

ΘΚΠ

the world > relative properties > number > geometry > line > [noun] > specifically in conic sections

parameter1656

polar1848

the world > relative properties > number > geometry > curve > [noun] > generated by or related to a point

polar1848

polar line1851

spline curve1946

1848 G. Salmon Treat. Conic Sections vi. 72 When the point..is outside the circle, the polar is the line joining the points of contact of real tangents.

1885 C. Leudesdorf tr. L. Cremona Elements Projective Geom. 201 The straight line s determined in this manner by the point S is called the polar of S with respect to the conic; and, reciprocally, the point S is said to be the pole of the straight line s.

1957 J. Glenn Tree of Math. xiv. 188 In virtue of the general properties of a correlation, the polars of all the points on a line a form a projectively related pencil of lines through the pole A.

1992 H. Eves Fund. Mod. Elem. Geom. ii. 95 Two points such that each lies on the polar of the other, for a given circle, are called conjugate points for the circle.

3. Geometry. In plural. Polar coordinates.

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the world > relative properties > number > geometry > geometric space > [noun] > division or marking of > axis > of coordinates > co-ordinate > system of

homogeneous co-ordinates1879

polar1920

1920 Proc. Royal Soc. A. 97 111 In plane polars the similar equations are [etc.].

1940 W. J. Eckert Punched Card Methods Sci. Computation xi. 100 For comparison with observation the rectangular coordinates must be converted into polars.

1992 Q. Jrnl. Mech. & Appl. Math. 45 555 (title) Convexivity considerations for the biharmonic equation in plane polars with applications to elasticity.

4. Botany. = polar nucleus n. at Compounds.

ΚΠ

1943 L. W. Sharp Fund. Cytol. x. 143 Sometimes the two polars have fused by the time the male nucleus arrives.

1995 Sexual Plant Reprod. 8 85 Nuclei of 8-nucleate sacs and of eggs and polars were 1C, indicating chromosomes were not duplicated before fertilization.

5. Science. A polarizing plate or prism. Usually in plural.

ΚΠ

?1949 A. F. Hallimond Man. Polarizing Microscope iii. 28 Polarizing units have long been commonly termed ‘nicols’, but it has now become necessary to employ a more general term... ‘Polarizer’ already has a special meaning, and the word ‘polar’ has therefore been used to designate any unit for producing or analysing plane-polarized light.

1956 Philos. Trans. (Royal Soc.) B. 240 59 (caption to plate 4) Note the banking of the discrete felspar crystals round this grain (Magn. × 6.6; crossed polars).

1972 R. Galopin & N. F. M. Henry Microsc. Study Opaque Minerals iii. 60 The dark-band is seen when the polars are crossed with a simple glass-plate reflector.

2002 Proc. National Acad. Sci. U.S.A. 99 4272 Observed in a polarizing microscope between parallel polars instead of either a polarizer or analyzer alone, the fluorescence polarization ratio rises to an unexpectedly high value.

6. A polar diagram showing the speed and direction of a moving object.

ΘΚΠ

society > communication > representation > a plastic or graphic representation > graphic representation > drawing plans or diagrams > [noun] > diagram > other types of diagram

map1797

base map1862

polar diagram1879

Gantt chart1918

pie diagram1921

pie chart1922

pie graph1930

histomap1931

process sheet1935

rose diagram1938

process chart1939

stereodiagram1945

wall chart1958

network1959

concept map1967

polar1975

mind map1987

1975 Nature 25 Sept. 307/2 The height to which a bird can zoom out of slope can be calculated if the flight polar of the bird and the strength of the lift are known.

1992 New Yorker 13 Apr. 95/3 A polar, which is normally produced while a yacht is still in development, is a computer-generated graph that shows the speed the craft should attain under various conditions and the heading it should assume in order to reach that speed.

2001 Jrnl. Exper. Biol. 204 1153 We measured the so-called glide super-polar, which is the envelope of fixed-wing glide polars over a range of forward speeds and sinking speeds.

7. Astronomy. A white dwarf that forms part of a binary star and has an intense magnetic field that causes it to accrete mass at its magnetic poles from its companion star and to emit strongly polarized light; a binary star containing such a white dwarf.The type is the star AM Herculis.

ΚΠ

1977 W. Krzemiński & K. Serkowski in Astrophysical Jrnl.: Lett. 216 45 The similarity of AN UMa to AM Her suggests that they both represent a very distinct type of object which, because of high polarization, we propose be called a ‘polar’.

1992 S. P. Maran Astron. & Astrophysics Encycl. 2/1 This happens in many accreting white dwarfs (the so-called polars and intermediate polars) and neutron stars (the x-ray pulsars).

2001 Origins of Life & Evol. of Biosphere 31 167 Magnetic white dwarfs and white dwarf binaries (Polars) can be highly circularly polarized but any effect on molecular clouds and star formation regions must rely on rare chance encounters.

8. Chemistry and Oil Industry. A polar organic compound.

ΚΠ

1984 Jrnl. Chromatogr. 288 187 Organic extracts of diesel exhaust particulates... The organic extracts are separated into aliphatics, aromatics and polars.

1991 Jrnl. High Resolution Chromatogr. 14 33 The oil contained 23% aromatics and 1% ‘polars’; some 99.5% of the aromatics were alkylated.

2004 Jrnl. Separation Sci. 27 311 This method has been applied to obtain amounts of saturates, aromatics, and polars in heavy oil distillates.

Compounds

polar air n. Meteorology cold air originating in high latitudes.

ΚΠ

1644 K. Digby Two Treat. i. xx. 176 Consequently, the polar ayre must draw a great trayne after it.

1789 Trans. Royal Irish Acad. 1788 2 Science 70 General Roy inferred that the polar air, though affected with the same temperature and pressure, was specifically heavier than in the middle zones.

1849 J. F. Cooper Sea Lions II. xiii. 177 This was a cheering temperature for those who had been breathing the polar air; and the influence of the north-east gale continued to increase.

1982 R. G. Barry & R. J. Chorley Atmosphere, Weather & Climate (ed. 4) v. 198 Warming of air masses over the north-eastern Atlantic is mainly of significance when polar or arctic air flows south-eastwards from Iceland.

polar anaemia n. anaemia developed by polar explorers as a result of the restricted diet and other conditions experienced in polar regions.

ΚΠ

1899 F. A. Cook in McClure's Mag. Nov. 15/1 The long darkness, the isolation, the tinned foods, the continued low temperature, with increasing storms and a high humidity, finally reduced our systems to what we will call polar anaemia. We became pale, with a kind of greenish hue.

1912 Evening Telegram (Elyria, Ohio) 2 Aug. 3/4 The malady comprised symptoms of scurvy, polar anaemia and severe frost bites.

2000 Hobart (Tasmania) Mercury (Nexis) 15 Apr. (Weekend section) 29 In extreme cases of polar anaemia, the mind becomes disturbed.

polar body n. Cell Biology each of the smaller cells resulting from the asymmetric division of an oocyte at the two meiotic divisions during gametogenesis, which break down and have no further genetic role.

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the world > life > biology > biological processes > procreation or reproduction > reproductive substances or cells > [noun] > ovum or ootid > polar body

polar body1882

polocyte1915

1882 Amer. Naturalist 16 654 In the female cell this is done by the process of budding, the result being the protrusion of one or more buds known as the polar bodies.

1927 J. B. S. Haldane & J. S. Huxley Animal Biol. ii. 60 In order to retain the large size of the egg, three of every four gametes produced are minute and non-functional, and are called polar bodies, while only one becomes a functional ovum.

1993 World & I Mar. 200/1 Yet another technique on the horizon, called polar body removal, may reveal the genetic makeup of an egg before it is fertilized.

polar circle n. either of the Arctic and Antarctic circles.

ΘΚΠ

the world > the earth > geodetic references > [noun] > latitude > polar circle

Arctic Circlec1540

polar circle1556

Antarctic Circle1587

polar line1658

polar1688

the world > the universe > celestial sphere > circle of celestial sphere > [noun] > lesser circle > polar circle

polar circle1556

1665 T. Herbert Some Years Trav. (new ed.) 5 These sorts of people freeze within the polar circles,..the Pole being their vertex, and the Æquator..their direct Horizon.

1776 E. Gibbon Decline & Fall I. x. 246 When his invincible Goths, armed with martial fanaticism, should issue in numerous swarms from the neighbourhood of the Polar circle, to chastise the oppressors of mankind.

1859 C. Darwin Origin of Species xi. 362 If we look at a globe, we shall see that under the Polar Circle there is almost continuous land from western Europe..to eastern America.

1977 A. Hallam Planet Earth 36/2 In between the Tropics and the polar circles are 43° of latitude in which the Sun is never vertically overhead.

polar coordinate n. Geometry either of a pair of coordinates (r, θ) defining the position of a point in a plane, where r is the length of the straight line connecting the point to a fixed reference point (the origin or pole), and θ is the angle between this line and a fixed reference line (the axis); (also) each of three coordinates in a three-dimensional extension (either spherical or cylindrical) of this system, involving a radial coordinate and one or two angular coordinates; usually in plural.

ΚΠ

1816 tr. S. F. Lacroix Elem. Treat. Differential & Integral Calculus 129 The variables in this equation are what Geometers have called polar co-ordinates.

1895 Electrician 27 Sept. 721/1 Dr. Fleming published a new and ingenious method of plotting wave forms with polar co-ordinates.

1962 D. R. Corson & P. Lorrain Introd. Electromagn. Fields iv. 154 Certain cases of symmetry are best treated in spherical polar coordinates.

polar diagram n. a diagram in which the length of the radius joining a fixed point to a point of a curve represents the magnitude of something (as the sensitivity of an aerial, or the brightness of a lamp) measured in the direction of the radius.

ΘΚΠ

society > communication > representation > a plastic or graphic representation > graphic representation > drawing plans or diagrams > [noun] > diagram > other types of diagram

map1797

base map1862

polar diagram1879

Gantt chart1918

pie diagram1921

pie chart1922

pie graph1930

histomap1931

process sheet1935

rose diagram1938

process chart1939

stereodiagram1945

wall chart1958

network1959

concept map1967

polar1975

mind map1987

1879 W. Thomson & P. G. Tait Treat. Nat. Philos. (new ed.) I: Pt. i. §134 Another closed or open polygon, constituting what is called the polar diagram to the given polygon.

1923 R. Glazebrook Dict. Appl. Physics IV. 429/2 These diagrams are what are generally termed ‘polar diagrams of light distribution’.

1962 A. Nisbett Technique Sound Studio i. 20 (caption) In a polar diagram such as this the curve indicates the output of the microphone for a given sound arriving from any angle.

polar dial n. a sundial whose gnomon lies in a plane containing the earth's axis.

ΘΚΠ

the world > time > instruments for measuring time > [noun] > sundial

chilindrec1386

dialc1425

sundial1555

clocka1562

cylinder1593

horoscope1623

compass-dial1632

moon dial1664

ring dial1667

heliotrope1669

pole-dial1669

sciatheric1682

spot dial1687

polar dial1688

sun clock1737

meridian ring1839

solarium1842

journey-ring1877

scratch dial1914

1688 G. Sinclair Princ. Astron. & Navigation xv. 72 The end or extremity of their Gnomons, upon their Horizontal Dialls, which are our Polar Dialls, describe the whole Year.

1737 C. Leadbetter Mechanick Dialling ix. 34 This Dial is called by some Authors an Equinoctial Dial, and by others a Polar Dial.

2001 Contra Costa (Calif.) Times (Nexis) 2 June c1 An aluminum polar dial. Gnomon has the profile of the Golden Gate Bridge.

polar diameter n. Astronomy the diameter of a planet measured from pole to pole.

ΚΠ

1694 Philos. Trans. (Royal Soc.) 18 253 Mr. Newton has shown that his [sc. Jupiter's] Polar Diameter is to that of his Equinoctial as 40 to 41 nearly.

1738 W. Deane Descr. Copernican Syst. 18 The Polar Diameter, or Axis, is to the Equatorial one, as 689 to 692.

1815 J. Smith Panorama Sci. & Art I. 277 The polar diameter of the earth.

1970 Jrnl. Brit. Astron. Assoc. 80 179 If ε is the amount of flattening, a is the equatorial diameter and b the polar diameter, then ε = 1 − b/a.

polar distance n. Astronomy the angular distance of a point on a sphere from the nearer pole (equal to the complement of the declination or latitude).

ΘΚΠ

the world > the universe > celestial sphere > [noun] > pole > polar distance

polar distance1652

co-declination1661

1652 S. Foster Posthuma Fosteri: Descr. Ruler xxii. 75 Measure EP upon your Scale of Chords, it will there give you the polar distance.

1754 J. Robertson Elements Navigation I. v. v. 236 EO = (HO − HE =) 13° 27′, is the decl. sought; which is north, as the altitude exceeds the co-lat.; consequently the polar distance OP = 76° 33′.

1974 Philos. Trans. (Royal Soc.) A. 276 70 The text gives..measurements in degrees..for the principal stars in the group; i.e. the hour-angle of the principal star..and the north polar distance.

polar equation n. Geometry an equation of a curve or surface expressed in polar coordinates.

ΚΠ

1813 Philos. Trans. (Royal Soc.) 103 12 By the polar equation of the curve, SQ = ^p/ ₂. cosec.(^MSQ/ ₂)².

1848 G. Salmon Treat. Conic Sections ii. 25 To find the polar equation of a right line.

1989 Encycl. Brit. XXVIII. 888/1 The circle x² + y² = a² has the polar equation (r cos θ)² + (r sin θ)² = a², which reduces to r = a.

polar flattening n. Astronomy the extent to which the polar diameter of a planet is shorter than the mean equatorial diameter.

ΘΚΠ

the world > the universe > planet > [noun] > part of planet > polar flattening

polar flattening1784

compression1820

1784 Philos. Trans. (Royal Soc.) 74 265 A little of the polar flattening is visible, so as to admit of no doubt.

1895 Astrophysical Jrnl. 2 136 Micrometric measures of the diameters of Mars..give as the most probable value for the equatorial diameter of the planet at distance unity: 9″.40 ± ·007; for the polar one: 9″.35 ± ·005; and for the polar flattening ¹/ ₁₉₀ of the equatorial diameter.

1954 Times 25 June 5/6 Dr. E. C. Slipher..has the task of determining accurately the diameter of Mars and the extent of its polar flattening.

2000 Isis 91 758/2 In addition, he made spectacular discoveries with a long-focus lens: the polar flattening and axial rotation of Jupiter.

polar fleece n. chiefly North American (originally) a thick woollen fabric (rare); (now, a proprietary name for) a synthetic fabric with a thick, soft pile, used esp. to make warm outer clothing and blankets; a jacket made of this.

ΚΠ

1945 Council Bluffs (Iowa) Nonpareil 7 Sept. 6/5 (advt.) 100% virgin wool Polar Fleece in log-brown, spruce-green, [etc.].

1983 Mountain Democrat (Placerville, Calif.) 28 Dec. 2/4 (advt.) Polar fleece $6.98 yd.

1996 Motoring & Leisure Feb. 26 (advt.) She wears a reversible jacket, a polar fleece with bleached polycotton in a blouson style.

2002 Nat. Home July 31/2 Polyester fleece, also known as polar fleece or micro fleece, seems to be the only fabric that really insulates and repels dampness.

polar front n. Meteorology a front between polar and equatorial air masses.

ΘΚΠ

the world > the earth > weather and the atmosphere > movements and pressure conditions > [noun] > uniform body of air > boundary of > specific

polar front1920

cold front1921

warm front1921

1920 V. Bjerknes in Nature 24 June 524/1 This line shows how far the cold air has succeeded in penetrating; it is a kind of polar front line.]

1920 V. Bjerknes in Nature 24 June 524/2 All meteorological events of the temperate zone..are derived from the general atmospheric circulation..as we know it from the polar front.

1973 R. G. Perry & A. H. Perry Synoptic Climatol. iii. 184 The classical view of tropical and polar air, separated by the polar front, does not accord well with modern knowledge of the general circulation.

1997 Independent 17 Sept. (Eye section) 10/5 Polar easterlies meet the prevailing westerlies at the polar front, which is where most of our chilly weather comes from.

polar hare n. the Arctic hare, Lepus arcticus, which is found in the Arctic areas of North America and has a coat that turns white in winter.

ΘΚΠ

the world > animals > mammals > group Unguiculata or clawed mammal > order Lagomorpha (rabbits and hares) > [noun] > family Leporidae > genus Lepus (hares) > lepus timidus (arctic hare)

varying hare1781

blue hare1784

polar hare1792

Arctic hare1821

mountain hare1879

1792 G. Cartwright Jrnl. Trans. & Events II. 76 This sort, in my opinion, ought rather to be called the mountain, than the polar hare.

1823 J. Franklin Narr. Journey Shores Polar Sea 664 The Polar hare appears to vary much in size, and consequently in weight.

1933 H. Ingstad Land of Feast & Famine v. 85 The ‘snowshoe hare’..is somewhat smaller than the..polar hare found up on the Barrens.

1965 Reno (Nevada) Evening Gaz. 25 Nov. 44/2 Rats and mice have reached there [sc. the Faeroe Islands] from ships and polar hare is imported.

polar lights n. (also polar light) the aurora borealis; the aurora australis.

ΚΠ

1841 Sydney Herald 19 Apr. 2/3 Aurora Australis. On the evening of the 10th instant, between the hours of eight and eleven, we had a very beautiful display of the ‘polar lights’.

1953 Council Bluffs (Iowa) Nonpareil 1 May 12/2 Polar lights are to be seen in some half dozen forms, the most common one being the arch.

1992 S. P. Maran Astron. & Astrophysics Encycl. 178/2 The aurora or the polar light is a magnificent, colorful, heavenly display that rewards those who defy the long and dark polar nights.

Polar medal n. (in the United Kingdom and Commonwealth countries) a decoration awarded for distinguished service (now of at least ten years) to those exploring and working in polar regions, instituted by Edward VII in 1904 to acknowledge the return of Scott's first expedition to the Antarctic.

ΚΠ

1904 Times 12 Sept. 8/2 (heading) New Polar medal... His Majesty the King has been graciously pleased to direct that a new medal for service in the Polar regions shall be struck.

1945 Geogr. Jrnl. 106 197 I have had to advise the Board on the question of the award of the Polar Medal.

1998 Guardian 14 July i. 18/4 The contribution to radar development by research on the ionosphere, coupled with glaciological discoveries and survey, earned each member of our team the Polar medal.

polar nucleus n. Botany (in angiosperm reproduction) either of the two haploid nuclei which move from the poles of the embryo sac to the centre and fuse with the male gamete to form the triploid primary endosperm nucleus.

ΚΠ

1882 S. H. Vines in tr. F. G. J. von Sachs Text-bk. Bot. (ed. 2) 581 In some instances the two polar nuclei meet, not in the centre, but towards the upper end of the embryo-sac.

1945 Q. Rev. Biol. 20 246/1 It was at first supposed that suppression of meiosis, or parthenogamy from a polar nucleus, might cause their appearance.

1992 M. Ingrouille Diversity & Evol. Land Plants 122 A double fertilization occurs with the formation of a diploid zygote (sperm nucleus plus egg) and a triploid endosperm nucleus (male gamete plus two polar nuclei).

polar orbit n. an orbit of a spacecraft or satellite that passes over the polar regions of a celestial object; spec. one whose plane contains the polar axis.

ΘΚΠ

society > travel > air or space travel > space flight > [noun] > a space shot or flight > course or trajectory of spacecraft > orbiting > types of orbit

parking orbit1941

polar orbit1956

transfer orbit1961

Molniya orbit1981

1956 Sci. Monthly July 16/1 In the polar orbit, however, the rotation of the earth causes the track of the satellite over the ground to spiral around in a complicated fashion.

1961 Times Rev. Industry Feb. 26/3 There are a number of possible satellite systems using polar, inclined and equatorial orbits.

1995 Denver Post 27 May c1/5 The agency maintains four satellites (two in polar orbit and one in ‘geostationary’ position over each coast).

polar-orbiting adj. that moves in a polar orbit.

ΚΠ

1958 Appeal-Democrat (Marysville–Yuba City, Calif.) 31 Dec. 5/7 The first Polar-orbiting satellite.

1963 Science 4 Jan. 36/1 There are two members of the OGO family: EGO (Eccentric Geophysical Observatory) and POGO (Polar Orbiting Geophysical Observatory).

1994 GPS World Apr. 22/2 Instruments used by ARGOS to determine buoy positions and to telemeter their data are carried on two polar-orbiting NOAA satellites.

polar plant n. the compass plant, Silphium laciniatum (family Asteraceae ( Compositae)), a tall, deep-rooted North American plant bearing large flowers similar to sunflowers and leaves that face north and south.

ΘΚΠ

the world > plants > particular plants > plants and herbs > according to family > Compositae (composite plants) > [noun] > compass-plant or silphium

silphium1771

turpentine weed1819

rosinweed1831

resinweed1838

polar plant1842

compass-flower1847

compass-plant1848

cup-plant1848

pilot weed1848

turpentine shrub-

1842 Farmer's Cabinet 15 Nov. 111/2 At mid-day, the plane of the Polar plant passes through the sun, and thus it shuns the light.

1963 Lima (Ohio) News 26 Apr. 15/2 The tall, erect leaves of the Silphium laciniatum (compass plant, pilot weed, polar plant, rosin weed) stand nearly vertical.

1996 Chiltern Seeds Catal. 219 Compass Plant, Pilot Weed, Polar Plant. The most famous plant from the American Prairies, this is an aristocratic species growing to 6 ft. or more.

polar projection n. a projection of the earth's surface or of the celestial sphere on to a plane in which the centre of projection is one of the poles.

ΚΠ

1625 N. Carpenter Geogr. Delineated i. vii. 182 (Polar projection) This kinde of proiection, though more vnusuall,..wants not his speciall vse in describing the parts of the earth neare the Pole.

1717 J. Green Constr. Maps & Globes i. iv. 22 The Stereographick Projection of the Sphere upon the Plane of the Equator, commonly call'd the Polar Projection.

1866 Jrnl. Royal Geogr. Soc. 10 221 Among them a chart of the southern hemisphere on the Polar Projection, illustrative of the ice-drift during the different seasons.

1960 Times 16 Nov. 13/6 The light-blue flag of the United Nations with its polar projection of the world in white.

2003 National Art Coll. Fund Rev. 2002 119/1 In the arch above is a celestial planisphere, engraved with a polar projection of most of the known fixed stars.

polar reciprocal n. a curve such that the polar of each point with respect to a given conic is tangential to another curve; (also) a polygon such that the polar of each point is a side of another given polygon; cf. sense reciprocal adj. 7a(b).Used analogously in spaces of higher dimension.

ΚΠ

1845 Cambr. Math. Jrnl. 4 127 Two cones may be drawn, and the vertices of these lie in the line which is the polar reciprocal of the line of intersection of the two planes.

1885 C. Leudesdorf tr. L. Cremona Elements Projective Geom. 240 Two curves..such that each is the locus of the poles of the tangents of the other, and at the same time also the envelope of the polars of the points of the other, are said to be polar reciprocals one of the other with respect to the auxiliary conic.

1940 Amer. Math. Monthly 47 243 Since OK·OX is constant, the envelope of w´ is the polar reciprocal of the locus of X.

1995 Mathematica Pannonica 6 77 (title) On the area sum of a convex polygon and its polar reciprocal.

2006 Wave Motion 43 288 Another surface, called the wave surface, is the polar reciprocal of the slowness surface.

polar surface n. Geometry a surface related to a given surface and a given point in a way analogous to the way a polar ( A. 2a) is related to a curve.

ΚΠ

1865 Philos. Trans. (Royal Soc.) 155 761 With regard to this ellipsoid the wave-surface is its own polar surface, i.e. the polar plane of any point of the surface touches it in another point.

1950 Proc. Amer. Math. Soc. 1 328 In the elliptic case it is interesting to consider the polar surface Sⁿ⁻¹(π/2) to the given Sⁿ⁻¹.

1970 Ann. Math. 92 371 The distance on S³ from η(a, 0) to η(b, 0), i.e., the distance between the corresponding points on the polar surface.

polar vector n. Mathematics a vector which changes sign when the signs of all its components are changed; cf. axial vector at vector n. 2a.

ΚΠ

1903 Nature 22 Oct. 610/1 This algebra..does not discriminate between ‘polar’ vectors, e.g. forces and ‘axial’ vectors, e.g. couples.

1968 M. S. Livingston Particle Physics v. 101 Angular momentum is an axial vector quantity, unlike linear momentum which is a polar vector.

polar wander n. Geology = polar wandering n.

ΘΚΠ

the world > the earth > geodetic references > [noun] > pole > axis > movement

nutation1703

pendulation1908

polar wandering1909

polar wander1957

1957 Philos. Trans. (Royal Soc.) A. 250 142 The rate of polar wander is very small compared with the average frequency of reversal of the geomagnetic field.

2001 A. G. Smith in R. Riding & A. Yu. Zhuravlev Ecol. Cambrian Radiation ii. 19 Some fundamental change in the behavior of the earth for this period, e.g...large components of ‘true’ polar wander, or a marked change in obliquity or climate.

polar wandering n. Geology the slow, erratic movement of the earth's poles relative to the continents which is thought to have occurred throughout geological time and is ascribed largely to continental drift; (in extended use) a corresponding movement on other planets.

ΘΚΠ

the world > the universe > planet > [noun] > part of planet > polar wandering

polar wandering1909

the world > the earth > geodetic references > [noun] > pole > axis > movement

nutation1703

pendulation1908

polar wandering1909

polar wander1957

1909 Proc. Royal Soc. A. 82 90 ‘We need not wonder’ that the amplitudes of the polar wanderings ‘should often vary by 5 or 10 metres in the course of a few weeks or months.’

1924 J. G. A. Skerl tr. A. Wegener Orig. Continents & Oceans viii. 123 Extensive, even if slow, polar wanderings are then able to take place.

1973 Science 9 Mar. 997 Polar wandering during the past 10⁸ years may be recorded by unique quasi-circular structures in the polar regions of Mars.

1985 Cambr. Encycl. Life Sci. xii. 307/1 These ‘polar wandering curves’ are different for each continent, which confirms that the continents have actually moved relative to one another.

This entry has been updated (OED Third Edition, September 2006; most recently modified version published online March 2022).

单词	polar
释义	polaradj.n. Brit. /ˈpəʊlə/, U.S. /ˈpoʊlər/ Forms: 1500s pollard, 1500s– polar. Origin: Of multiple origins. Partly a borrowing from Latin. Partly formed within English, by derivation. Etymons: Latin polaris ; pole n.², -ar suffix¹. Etymology: Partly < post-classical Latin polaris of the sky or heaven (from 8th cent. in British sources), of or relating to the North or South Pole or pole star (a1275 in a British source; < classical Latin polus pole n.² + -āris -ar suffix¹), and partly (in later use) < pole n.² + -ar suffix¹. Compare Middle French, French polaire (1432 or earlier), Spanish polar (1507 or earlier), Italian polare (1573), all earliest in sense A. 1a.In sense B. 2 after French polaire du point (J. D. Gergonne 1812, in Ann. des math. 3 297). With polar body n. compare French globule polaire (1875 or earlier; usually in plural). With polar circle n. compare Middle French, French cercle polaire (1432 or earlier). In polar coordinate n. probably after French coordonnée polaire (1811 or earlier; usually in plural). With polar vector n. compare French vecteur polaire (1901 or earlier). A. adj. 1. a. Of or relating to the North or South Pole of the earth (or another celestial object), or the poles of the celestial sphere; situated near or aligned with respect to a pole; characteristic of or occurring in the regions near a pole. Cf. pole n.² 1.Recorded earliest in polar circle n. at Compounds. ΘΚΠ the world > the universe > celestial sphere > [adjective] > pole polar1556 polary1559 the world > the earth > geodetic references > [adjective] > pole polar1556 polary1559 subpolar1685 circumpolar1696 polifugal1744 poleward1848 bipolar1896 1556 R. Record Castle of Knowl. 41 Recken from one of the poles..23 degrees and an halfe,..draw a circle of that circuit about eche Pole... These circles maye well bee called Pole circles, or Polar circles. 1595 J. Davis Seamans Secrets ii. sig. H4^v The Artick Polar Circle is one of the lesser circles, deuiding the sphere into two vnequall partes. 1667 J. Milton Paradise Lost x. 289 As when two Polar Winds..together drive Mountains of Ice. View more context for this quotation a1711 T. Ken Hymnotheo iv, in Wks. (1721) III. 120 Devotion cold as Polar Ice was grown. 1786 A. Becket Trip to Holland 41 Do we not find in the Polar regions the same degree of barbarism that marks the inhabitants of the Torrid Zone? 1790 H. J. Pye Amusement 7 The lengthen'd horrors of a polar night, Where..No dawning light shall gild the mountain's brow. 1856 E. K. Kane Arctic Explor. I. xxiii. 302 Well known to the Polar traveller. 1878 T. H. Huxley Physiography (ed. 2) 178 The cold polar waters sink by their density. 1937 J. E. Tilden Algae & their Life Relations (ed. 2) 22 One must expect to find fewer green algae in the land of long, dark nights—the polar regions. 1968 Solar Physics 3 321 The appearance of the solar corona over the poles at time of low solar activity is dominated by the presence of polar plumes. 2001 Time 17 Dec. 16 The circling Arctic winds weaken and cold air descends from the polar region. b. Analogous to the Pole Star or to the poles of the earth in serving to guide, direct, or impel others. ΘΚΠ society > authority > control > [adjective] > leading or guiding conductive1528 directional1612 guidinga1616 leadinga1628 manuducent1677 conducting1710 bear-leading1748 bear-leading1766 polar1791 1791 T. Paine Rights of Man i. 117 When a man in a long cause attempts to steer his course by any thing else than some polar truth or principle, he is sure to be lost. 1801 Ann. Reg. 1799 (Otridge ed.) ii. App. to Chron. 156/1 Universal Emancipation, with Representative Legislature, was the polar principle which guided the Society of United Irishmen. 1858 T. Carlyle Hist. Friedrich II of Prussia I. i. i. 7 A king over men; whose movements were polar, and carried..those of the world along with them. 1899 Expositor Jan. 51 Both the Church and the world depend in crisis on the man of insight:..the polar primary man. 1927 V. L. Parrington Colonial Mind 152 To one cardinal principle Edwards was faithful—the conception of the majesty and sufficiency of God; and this polar idea provides the clue to both his philosophical and theological systems. 2000 B. Meeks Narr. Resistance 163 One needs also to probe the extent to which Cuba, Nicaragua, Grenada, and the rest of the Left that did not achieve state power, departed from some abstract, polar notion of authoritarianism. c. Of clothing: designed to be worn in very cold weather such as prevails in polar regions. Cf. polar fleece n. at Compounds. ΚΠ 1885 Messenger (Indiana, Pa.) 9 Dec. 3/6 Arctic Overshoes for men and women... Polar boots at $1,25 per pair. 1926 Geogr. Jrnl. 68 45 Articles, such as..polar clothing. 1978 Newport (Rhode Island) Daily News 13 Nov. 7/1 In the middle of a record cold snap, Charles receives an expensive polar suit from his parents. 2003 Weekend Austral. (Nexis) 27 Dec. b36 It was far too cold to lounge about in a Como turtleneck, so we got about in long johns and thermals and..polar jackets. 2. a. Originally: designating the property of some substances of aligning themselves in the direction of the earth's poles; magnetic. In later use also: of or relating to one of the poles of a magnet; having magnetic poles. Cf. pole n.² 6. ΘΚΠ the world > matter > physics > electromagnetic radiation > magnetism > magnetic devices or materials > [adjective] > polar polar1613 polary1646 1613 M. Ridley Short Treat. Magneticall Bodies 62 The iron barres..being..placed North and South, do receive a polar vertue, and directory faculty. 1692 T. P. Blount Ess. 88 The Polar Vertue of the Loadstone was unknown to the Ancients. 1705 E. Scarburgh Eng. Euclide 2 In Loadstones it is commonly known that there are Polar Points, called North and South. 1821 H. Davy in Philos. Trans. (Royal Soc.) 111 16 A body was moved round the circle from the north to the south poles of the same wire... It was perfectly evident..that as many polar arrangements may be formed as chords can be drawn in circles surrounding the wire. 1860 J. Tyndall Glaciers of Alps i. xx. 142 I examined the stones..and found them strongly polar. 1872 W. Thomson Reprint Papers 421 A polar magnet, as I shall henceforth call anything magnetized after the manner of a loadstone or a steel magnet. 1891 S. P. Thompson Electromagnet 39 The pole or polar region of a magnet is simply that part of the surface of a magnet whence the internal magnetic lines emerge into the air. 1925 H. C. Booth tr. F. Auerbach Mod. Magnetics (U.K. ed.) ii. 35 Small molecular magnets, each of which possesses a definite moment ml (the product of the polar strength and the polar distance). 2003 Times (Nexis) 28 May (Times2 section) 4 Fisk makes eye contact as though he is trying to force together the polar opposites of a magnet. †b. Science. Designating an arrangement or orientation of particles in a particular direction (like iron filings under the influence of a magnet). Obsolete. ΘΚΠ the world > matter > chemistry > chemical structure or stereochemistry > [adjective] > of or relating to polarization polar1776 1776 B. Higgins Philos. Ess. Light I. p. xxvii Estimations of the force of this attraction in contact, and at given distances, in fortuitous, and in polar arrangement of the atoms. 1850 W. R. Grove On Correlation Physical Forces (ed. 2) 36 At the point of maximum density the molecules of these bodies assume a polar or crystalline condition. 1870 H. Spencer Princ. Psychol. (ed. 2) I. v. ii. 517 Adjacent molecules will be unsymmetrically placed..they will not stand in polar order. 3. Mathematics. Relating to or referred to a pole (pole n.² 8); of the nature of a polar (sense B. 2).See also polar coordinate n. at Compounds, polar curve n., polar diagram n. at Compounds.Recorded earliest in polar equation n. at Compounds. ΘΚΠ the world > relative properties > number > geometry > point > [adjective] umbilical1728 polar1813 umbilicar1843 connectant1863 stigmatic1863 cuspidal1874 tropal1875 cusped1879 copunctal1896 open1896 perfect1897 closed1902 1813 Philos. Trans. (Royal Soc.) 103 12 By the polar equation of the curve, SQ = ^p/ ₂. cosec.(^MSQ/ ₂)². 1879 W. Thomson & P. G. Tait Treat. Nat. Philos. (new ed.) I: Pt. i. §134 The polar figure to any continuous curve on a spherical surface is the locus of the ultimate intersections of great circles equatorial to points taken infinitely near each other along it. 1972 M. Kline Math. Thought xxxv. 845 One of Poncelet's objectives in studying polar reciprocation with respect to a conic was to establish the principle of duality. 1991 C. B. Boyer & U. C. Merzbach Hist. Math. (ed. 2) viii. 127 If point P on the spiral is chosen.., the polar subtangent OQ will be precisely equal to quarter of the circumference of the circle of radius OP. 4. a. Of or designating forces acting in opposing directions. Chiefly figurative. ΘΚΠ the world > space > direction > [adjective] > having opposite direction > of forces polar1818 polaristic1859 polaric1863 1818 S. T. Coleridge Friend (new ed.) I. 155 There is, strictly speaking, no proper opposition but between the two polar forces of one and the same power. 1862 W. R. Grove On Correlation Physical Forces (ed. 4) 38 Cases where a dual or polar character of force is manifested. 1863 E. V. Neale Analogy Thought & Nature 45 The thought of centres of force becomes that of polar force, where the most entire union is produced by the most complete opposition. 1913 G. F. Moore Hist. Relig. I. iv. 71 The Chinese philosophy of nature, with its two polar forces, Yang and Yin. 1983 J. L. Sundquist Dynamics Party Syst. (rev. ed.) v. 79 The Republican leaders, who were a polar force on the one issue, acted as moderate centrists on the others. 1996 N.Y. Rev. Bks. 3 Oct. 24/1 The polar forces of deed and reflection that we find in the heroes of classical German drama. b. Directly opposite in character, action, or tendency; representing an extreme case. ΘΚΠ the world > relative properties > relationship > contrariety or contrast > [adjective] > opposite or opposed turneda1325 reversedc1390 contrary1413 opposeda1500 oppositea1513 inverted1563 counter1596 diametrical1613 contraposed1620 oppositive1622 averse1623 diagonial1624 contrarying1628 diametrala1631 conversive1636 Antipodian1640 converted1640 exadverse1647 Antarctic1651 Antipodean1651 antipodal1664 in reverse1694 contradictory1736 converse1794 antithesistic1801 contravening1802 diametric1802 reverse1828 polar1832 antipodist1844 antithetic1864 other-sided1879 antipodic1881 1832 Blackwood's Edinb. Mag. June 998 Rusticity and Urbanity are polar opposites. 1841 T. Carlyle On Heroes iii. 157 Dante felt Good and Evil to be the two polar elements of this Creation, on which it all turns. 1853 T. De Quincey Autobiogr. Sketches vii. 224 Talent and genius..are not merely different; they are in polar opposition to each other. 1935 H. Read Green Child 238 Order and Disorder might be taken as the polar opposites that together constituted a single harmonious whole. 1972 Sci. Amer. Jan. 35/1 Although sex-role ideologies form a continuum, we grouped the respondents into two polar categories, which we labeled ‘traditional’ and ‘contemporary’. 1988 Q. N. Myrvik & R. S. Weiser Fund. Med. Bacteriol. & Mycol. (ed. 2) xxvii. 401 Most cases of leprosy belong to one of two polar forms of the disease, lepromatous leprosy..and tuberculoid type leprosy. 1994 J. Edwards Multilingualism (1995) vii. 177 The very terms pluralism and assimilation seem not, after all, to be such polar opposites as might first be thought. 5. a. Physical Chemistry. (Of chemical decomposition) occurring at one or other pole in electrolysis; relating to the poles of a battery or cell. Cf. pole n.² 10. Now rare. ΘΚΠ the world > matter > physics > electromagnetic radiation > electricity > galvanism, voltaism > [adjective] > relating to poles polar1826 the world > matter > physics > electromagnetic radiation > electricity > electric polarization > [adjective] > relating to poles polar1826 1826 H. Davy in Philos. Trans. (Royal Soc.) 116 387 Conceiving that all decompositions might be polar, I electrised different compounds at the different extremities. 1833 M. Faraday in Philos. Trans. (Royal Soc.) 123 42 However distinct all these actions may be from true polar electro-chemical decompositions, they are still highly important, and well worthy of investigation. 1851 Abstr. Papers Royal Soc. 1843–50 5 501 The elements constituting the voltaic battery assume polar tension before the circuit is completed, even in a single cell. 1892 T. O'C. Sloane Standard Electr. Dict. (1893) 454 Polar region, in electro-therapeutics the area or region of the body near the therapeutic electrode. 1911 Physical Rev. 32 215 The optimum current depended on the polar distance and occurred at increasing current densities as the polar distance was increased. b. Chemistry. Involving or relating to the separation of positive and negative electric charge between different parts of a molecule, atom, etc.; spec. (a) (of a chemical bond) ionic; (esp. of a solid) composed of ions; (b) (of a covalent bond) such that the electron charge density is unequally shared between the two atoms; (of a molecule or group) having an electric dipole moment; (esp. of a liquid) consisting of such molecules. ΘΚΠ the world > matter > chemistry > chemical bonding > [adjective] > of or relating to polar bonding polar1882 1882 Amer. Naturalist 16 554 Each [molecule] must be composed of acid and basic, or positive and negative constituents, and thus be a chemically polar organism. 1913 Jrnl. Amer. Chem. Soc. 35 1443 In the preceding paragraphs we have suggested that there are two distinct types of union between atoms: polar, in which an electron has passed from one atom to the other, and non-polar, in which there is no motion of an electron. 1927 N. V. Sidgwick Electronic Theory of Valency iv. 52 Polar or ionizable linkages between the oppositely charged ions of a salt. 1936 S. Glasstone Recent Adv. Gen. Chem. vi. 257 Polar and non-polar liquids are generally immiscible. 1951 I. L. Finar Org. Chem. ii. 14 A symmetrical molecule is non-polar, although it may contain polar bonds. 1960 D. Nachmansohn in G. H. Bourne Struct. & Function Muscle II. v. 234 The carbonyl group has a marked polar character. 1974 J. S. Blakemore Solid State Physics (ed. 2) iv. 338 Optical phonon scattering..is especially important for a solid with a polar (partially or completely ionic) lattice. 1999 C. Mendelson Home Comforts xxviii. 383/2 Water is very highly polar. Polar substances remove stains caused by water-soluble substances. 6. Biology. Of or relating to the poles of a cell, organ, etc. Cf. pole cell n. at pole n.² Compounds. Now chiefly in polar body n. at Compounds. ΘΚΠ the world > life > biology > substance > cell > parts of cell > [adjective] > regions polar1869 periplasmic1967 1869 Nature 30 Dec. 247/1 The ova when deposited never present the least trace of the polar-cell. 1888 G. Rolleston & W. H. Jackson Forms Animal Life (ed. 2) Introd. 22 A clear spot, the polar spot or corpuscle, may appear at each pole of the spindle. 1898 Arch. Surg. 9 356 Opacities in the vitreous and posterior polar cataract had made their appearance. 1988 Q. N. Myrvik & R. S. Weiser Fund. Med. Bacteriol. & Mycol. (ed. 2) ii. 37 Polar flagella exist either as a tuft of flagella (lophotrichous) or a single flagellum (monotrichous). B. n. †1. Astronomy. = polar circle n. at Compounds. Obsolete. rare. ΘΚΠ the world > the earth > geodetic references > [noun] > latitude > polar circle Arctic Circlec1540 polar circle1556 Antarctic Circle1587 polar line1658 polar1688 1688 G. Sinclair Princ. Astron. & Navigation 33 The polars..are two in number, the polar artick, and the polar antartick. 2. Geometry. The straight line joining the two points at which tangents from a given point touch a conic section. ΘΚΠ the world > relative properties > number > geometry > line > [noun] > specifically in conic sections parameter1656 polar1848 the world > relative properties > number > geometry > curve > [noun] > generated by or related to a point polar1848 polar line1851 spline curve1946 1848 G. Salmon Treat. Conic Sections vi. 72 When the point..is outside the circle, the polar is the line joining the points of contact of real tangents. 1885 C. Leudesdorf tr. L. Cremona Elements Projective Geom. 201 The straight line s determined in this manner by the point S is called the polar of S with respect to the conic; and, reciprocally, the point S is said to be the pole of the straight line s. 1957 J. Glenn Tree of Math. xiv. 188 In virtue of the general properties of a correlation, the polars of all the points on a line a form a projectively related pencil of lines through the pole A. 1992 H. Eves Fund. Mod. Elem. Geom. ii. 95 Two points such that each lies on the polar of the other, for a given circle, are called conjugate points for the circle. 3. Geometry. In plural. Polar coordinates. ΘΚΠ the world > relative properties > number > geometry > geometric space > [noun] > division or marking of > axis > of coordinates > co-ordinate > system of homogeneous co-ordinates1879 polar1920 1920 Proc. Royal Soc. A. 97 111 In plane polars the similar equations are [etc.]. 1940 W. J. Eckert Punched Card Methods Sci. Computation xi. 100 For comparison with observation the rectangular coordinates must be converted into polars. 1992 Q. Jrnl. Mech. & Appl. Math. 45 555 (title) Convexivity considerations for the biharmonic equation in plane polars with applications to elasticity. 4. Botany. = polar nucleus n. at Compounds. ΚΠ 1943 L. W. Sharp Fund. Cytol. x. 143 Sometimes the two polars have fused by the time the male nucleus arrives. 1995 Sexual Plant Reprod. 8 85 Nuclei of 8-nucleate sacs and of eggs and polars were 1C, indicating chromosomes were not duplicated before fertilization. 5. Science. A polarizing plate or prism. Usually in plural. ΚΠ ?1949 A. F. Hallimond Man. Polarizing Microscope iii. 28 Polarizing units have long been commonly termed ‘nicols’, but it has now become necessary to employ a more general term... ‘Polarizer’ already has a special meaning, and the word ‘polar’ has therefore been used to designate any unit for producing or analysing plane-polarized light. 1956 Philos. Trans. (Royal Soc.) B. 240 59 (caption to plate 4) Note the banking of the discrete felspar crystals round this grain (Magn. × 6.6; crossed polars). 1972 R. Galopin & N. F. M. Henry Microsc. Study Opaque Minerals iii. 60 The dark-band is seen when the polars are crossed with a simple glass-plate reflector. 2002 Proc. National Acad. Sci. U.S.A. 99 4272 Observed in a polarizing microscope between parallel polars instead of either a polarizer or analyzer alone, the fluorescence polarization ratio rises to an unexpectedly high value. 6. A polar diagram showing the speed and direction of a moving object. ΘΚΠ society > communication > representation > a plastic or graphic representation > graphic representation > drawing plans or diagrams > [noun] > diagram > other types of diagram map1797 base map1862 polar diagram1879 Gantt chart1918 pie diagram1921 pie chart1922 pie graph1930 histomap1931 process sheet1935 rose diagram1938 process chart1939 stereodiagram1945 wall chart1958 network1959 concept map1967 polar1975 mind map1987 1975 Nature 25 Sept. 307/2 The height to which a bird can zoom out of slope can be calculated if the flight polar of the bird and the strength of the lift are known. 1992 New Yorker 13 Apr. 95/3 A polar, which is normally produced while a yacht is still in development, is a computer-generated graph that shows the speed the craft should attain under various conditions and the heading it should assume in order to reach that speed. 2001 Jrnl. Exper. Biol. 204 1153 We measured the so-called glide super-polar, which is the envelope of fixed-wing glide polars over a range of forward speeds and sinking speeds. 7. Astronomy. A white dwarf that forms part of a binary star and has an intense magnetic field that causes it to accrete mass at its magnetic poles from its companion star and to emit strongly polarized light; a binary star containing such a white dwarf.The type is the star AM Herculis. ΚΠ 1977 W. Krzemiński & K. Serkowski in Astrophysical Jrnl.: Lett. 216 45 The similarity of AN UMa to AM Her suggests that they both represent a very distinct type of object which, because of high polarization, we propose be called a ‘polar’. 1992 S. P. Maran Astron. & Astrophysics Encycl. 2/1 This happens in many accreting white dwarfs (the so-called polars and intermediate polars) and neutron stars (the x-ray pulsars). 2001 Origins of Life & Evol. of Biosphere 31 167 Magnetic white dwarfs and white dwarf binaries (Polars) can be highly circularly polarized but any effect on molecular clouds and star formation regions must rely on rare chance encounters. 8. Chemistry and Oil Industry. A polar organic compound. ΚΠ 1984 Jrnl. Chromatogr. 288 187 Organic extracts of diesel exhaust particulates... The organic extracts are separated into aliphatics, aromatics and polars. 1991 Jrnl. High Resolution Chromatogr. 14 33 The oil contained 23% aromatics and 1% ‘polars’; some 99.5% of the aromatics were alkylated. 2004 Jrnl. Separation Sci. 27 311 This method has been applied to obtain amounts of saturates, aromatics, and polars in heavy oil distillates. Compounds polar air n. Meteorology cold air originating in high latitudes. ΚΠ 1644 K. Digby Two Treat. i. xx. 176 Consequently, the polar ayre must draw a great trayne after it. 1789 Trans. Royal Irish Acad. 1788 2 Science 70 General Roy inferred that the polar air, though affected with the same temperature and pressure, was specifically heavier than in the middle zones. 1849 J. F. Cooper Sea Lions II. xiii. 177 This was a cheering temperature for those who had been breathing the polar air; and the influence of the north-east gale continued to increase. 1982 R. G. Barry & R. J. Chorley Atmosphere, Weather & Climate (ed. 4) v. 198 Warming of air masses over the north-eastern Atlantic is mainly of significance when polar or arctic air flows south-eastwards from Iceland. polar anaemia n. anaemia developed by polar explorers as a result of the restricted diet and other conditions experienced in polar regions. ΚΠ 1899 F. A. Cook in McClure's Mag. Nov. 15/1 The long darkness, the isolation, the tinned foods, the continued low temperature, with increasing storms and a high humidity, finally reduced our systems to what we will call polar anaemia. We became pale, with a kind of greenish hue. 1912 Evening Telegram (Elyria, Ohio) 2 Aug. 3/4 The malady comprised symptoms of scurvy, polar anaemia and severe frost bites. 2000 Hobart (Tasmania) Mercury (Nexis) 15 Apr. (Weekend section) 29 In extreme cases of polar anaemia, the mind becomes disturbed. polar body n. Cell Biology each of the smaller cells resulting from the asymmetric division of an oocyte at the two meiotic divisions during gametogenesis, which break down and have no further genetic role. ΘΚΠ the world > life > biology > biological processes > procreation or reproduction > reproductive substances or cells > [noun] > ovum or ootid > polar body polar body1882 polocyte1915 1882 Amer. Naturalist 16 654 In the female cell this is done by the process of budding, the result being the protrusion of one or more buds known as the polar bodies. 1927 J. B. S. Haldane & J. S. Huxley Animal Biol. ii. 60 In order to retain the large size of the egg, three of every four gametes produced are minute and non-functional, and are called polar bodies, while only one becomes a functional ovum. 1993 World & I Mar. 200/1 Yet another technique on the horizon, called polar body removal, may reveal the genetic makeup of an egg before it is fertilized. polar circle n. either of the Arctic and Antarctic circles. ΘΚΠ the world > the earth > geodetic references > [noun] > latitude > polar circle Arctic Circlec1540 polar circle1556 Antarctic Circle1587 polar line1658 polar1688 the world > the universe > celestial sphere > circle of celestial sphere > [noun] > lesser circle > polar circle polar circle1556 1556 R. Record Castle of Knowl. 41 Recken from one of the poles..23 degrees and an halfe,..draw a circle of that circuit about eche Pole... These circles maye well bee called Pole circles, or Polar circles. 1665 T. Herbert Some Years Trav. (new ed.) 5 These sorts of people freeze within the polar circles,..the Pole being their vertex, and the Æquator..their direct Horizon. 1776 E. Gibbon Decline & Fall I. x. 246 When his invincible Goths, armed with martial fanaticism, should issue in numerous swarms from the neighbourhood of the Polar circle, to chastise the oppressors of mankind. 1859 C. Darwin Origin of Species xi. 362 If we look at a globe, we shall see that under the Polar Circle there is almost continuous land from western Europe..to eastern America. 1977 A. Hallam Planet Earth 36/2 In between the Tropics and the polar circles are 43° of latitude in which the Sun is never vertically overhead. polar coordinate n. Geometry either of a pair of coordinates (r, θ) defining the position of a point in a plane, where r is the length of the straight line connecting the point to a fixed reference point (the origin or pole), and θ is the angle between this line and a fixed reference line (the axis); (also) each of three coordinates in a three-dimensional extension (either spherical or cylindrical) of this system, involving a radial coordinate and one or two angular coordinates; usually in plural. ΚΠ 1816 tr. S. F. Lacroix Elem. Treat. Differential & Integral Calculus 129 The variables in this equation are what Geometers have called polar co-ordinates. 1895 Electrician 27 Sept. 721/1 Dr. Fleming published a new and ingenious method of plotting wave forms with polar co-ordinates. 1962 D. R. Corson & P. Lorrain Introd. Electromagn. Fields iv. 154 Certain cases of symmetry are best treated in spherical polar coordinates. polar diagram n. a diagram in which the length of the radius joining a fixed point to a point of a curve represents the magnitude of something (as the sensitivity of an aerial, or the brightness of a lamp) measured in the direction of the radius. ΘΚΠ society > communication > representation > a plastic or graphic representation > graphic representation > drawing plans or diagrams > [noun] > diagram > other types of diagram map1797 base map1862 polar diagram1879 Gantt chart1918 pie diagram1921 pie chart1922 pie graph1930 histomap1931 process sheet1935 rose diagram1938 process chart1939 stereodiagram1945 wall chart1958 network1959 concept map1967 polar1975 mind map1987 1879 W. Thomson & P. G. Tait Treat. Nat. Philos. (new ed.) I: Pt. i. §134 Another closed or open polygon, constituting what is called the polar diagram to the given polygon. 1923 R. Glazebrook Dict. Appl. Physics IV. 429/2 These diagrams are what are generally termed ‘polar diagrams of light distribution’. 1962 A. Nisbett Technique Sound Studio i. 20 (caption) In a polar diagram such as this the curve indicates the output of the microphone for a given sound arriving from any angle. polar dial n. a sundial whose gnomon lies in a plane containing the earth's axis. ΘΚΠ the world > time > instruments for measuring time > [noun] > sundial chilindrec1386 dialc1425 sundial1555 clocka1562 cylinder1593 horoscope1623 compass-dial1632 moon dial1664 ring dial1667 heliotrope1669 pole-dial1669 sciatheric1682 spot dial1687 polar dial1688 sun clock1737 meridian ring1839 solarium1842 journey-ring1877 scratch dial1914 1688 G. Sinclair Princ. Astron. & Navigation xv. 72 The end or extremity of their Gnomons, upon their Horizontal Dialls, which are our Polar Dialls, describe the whole Year. 1737 C. Leadbetter Mechanick Dialling ix. 34 This Dial is called by some Authors an Equinoctial Dial, and by others a Polar Dial. 2001 Contra Costa (Calif.) Times (Nexis) 2 June c1 An aluminum polar dial. Gnomon has the profile of the Golden Gate Bridge. polar diameter n. Astronomy the diameter of a planet measured from pole to pole. ΚΠ 1694 Philos. Trans. (Royal Soc.) 18 253 Mr. Newton has shown that his [sc. Jupiter's] Polar Diameter is to that of his Equinoctial as 40 to 41 nearly. 1738 W. Deane Descr. Copernican Syst. 18 The Polar Diameter, or Axis, is to the Equatorial one, as 689 to 692. 1815 J. Smith Panorama Sci. & Art I. 277 The polar diameter of the earth. 1970 Jrnl. Brit. Astron. Assoc. 80 179 If ε is the amount of flattening, a is the equatorial diameter and b the polar diameter, then ε = 1 − b/a. polar distance n. Astronomy the angular distance of a point on a sphere from the nearer pole (equal to the complement of the declination or latitude). ΘΚΠ the world > the universe > celestial sphere > [noun] > pole > polar distance polar distance1652 co-declination1661 1652 S. Foster Posthuma Fosteri: Descr. Ruler xxii. 75 Measure EP upon your Scale of Chords, it will there give you the polar distance. 1754 J. Robertson Elements Navigation I. v. v. 236 EO = (HO − HE =) 13° 27′, is the decl. sought; which is north, as the altitude exceeds the co-lat.; consequently the polar distance OP = 76° 33′. 1974 Philos. Trans. (Royal Soc.) A. 276 70 The text gives..measurements in degrees..for the principal stars in the group; i.e. the hour-angle of the principal star..and the north polar distance. polar equation n. Geometry an equation of a curve or surface expressed in polar coordinates. ΚΠ 1813 Philos. Trans. (Royal Soc.) 103 12 By the polar equation of the curve, SQ = ^p/ ₂. cosec.(^MSQ/ ₂)². 1848 G. Salmon Treat. Conic Sections ii. 25 To find the polar equation of a right line. 1989 Encycl. Brit. XXVIII. 888/1 The circle x² + y² = a² has the polar equation (r cos θ)² + (r sin θ)² = a², which reduces to r = a. polar flattening n. Astronomy the extent to which the polar diameter of a planet is shorter than the mean equatorial diameter. ΘΚΠ the world > the universe > planet > [noun] > part of planet > polar flattening polar flattening1784 compression1820 1784 Philos. Trans. (Royal Soc.) 74 265 A little of the polar flattening is visible, so as to admit of no doubt. 1895 Astrophysical Jrnl. 2 136 Micrometric measures of the diameters of Mars..give as the most probable value for the equatorial diameter of the planet at distance unity: 9″.40 ± ·007; for the polar one: 9″.35 ± ·005; and for the polar flattening ¹/ ₁₉₀ of the equatorial diameter. 1954 Times 25 June 5/6 Dr. E. C. Slipher..has the task of determining accurately the diameter of Mars and the extent of its polar flattening. 2000 Isis 91 758/2 In addition, he made spectacular discoveries with a long-focus lens: the polar flattening and axial rotation of Jupiter. polar fleece n. chiefly North American (originally) a thick woollen fabric (rare); (now, a proprietary name for) a synthetic fabric with a thick, soft pile, used esp. to make warm outer clothing and blankets; a jacket made of this. ΚΠ 1945 Council Bluffs (Iowa) Nonpareil 7 Sept. 6/5 (advt.) 100% virgin wool Polar Fleece in log-brown, spruce-green, [etc.]. 1983 Mountain Democrat (Placerville, Calif.) 28 Dec. 2/4 (advt.) Polar fleece $6.98 yd. 1996 Motoring & Leisure Feb. 26 (advt.) She wears a reversible jacket, a polar fleece with bleached polycotton in a blouson style. 2002 Nat. Home July 31/2 Polyester fleece, also known as polar fleece or micro fleece, seems to be the only fabric that really insulates and repels dampness. polar front n. Meteorology a front between polar and equatorial air masses. ΘΚΠ the world > the earth > weather and the atmosphere > movements and pressure conditions > [noun] > uniform body of air > boundary of > specific polar front1920 cold front1921 warm front1921 1920 V. Bjerknes in Nature 24 June 524/1 This line shows how far the cold air has succeeded in penetrating; it is a kind of polar front line.] 1920 V. Bjerknes in Nature 24 June 524/2 All meteorological events of the temperate zone..are derived from the general atmospheric circulation..as we know it from the polar front. 1973 R. G. Perry & A. H. Perry Synoptic Climatol. iii. 184 The classical view of tropical and polar air, separated by the polar front, does not accord well with modern knowledge of the general circulation. 1997 Independent 17 Sept. (Eye section) 10/5 Polar easterlies meet the prevailing westerlies at the polar front, which is where most of our chilly weather comes from. polar hare n. the Arctic hare, Lepus arcticus, which is found in the Arctic areas of North America and has a coat that turns white in winter. ΘΚΠ the world > animals > mammals > group Unguiculata or clawed mammal > order Lagomorpha (rabbits and hares) > [noun] > family Leporidae > genus Lepus (hares) > lepus timidus (arctic hare) varying hare1781 blue hare1784 polar hare1792 Arctic hare1821 mountain hare1879 1792 G. Cartwright Jrnl. Trans. & Events II. 76 This sort, in my opinion, ought rather to be called the mountain, than the polar hare. 1823 J. Franklin Narr. Journey Shores Polar Sea 664 The Polar hare appears to vary much in size, and consequently in weight. 1933 H. Ingstad Land of Feast & Famine v. 85 The ‘snowshoe hare’..is somewhat smaller than the..polar hare found up on the Barrens. 1965 Reno (Nevada) Evening Gaz. 25 Nov. 44/2 Rats and mice have reached there [sc. the Faeroe Islands] from ships and polar hare is imported. polar lights n. (also polar light) the aurora borealis; the aurora australis. ΚΠ 1841 Sydney Herald 19 Apr. 2/3 Aurora Australis. On the evening of the 10th instant, between the hours of eight and eleven, we had a very beautiful display of the ‘polar lights’. 1953 Council Bluffs (Iowa) Nonpareil 1 May 12/2 Polar lights are to be seen in some half dozen forms, the most common one being the arch. 1992 S. P. Maran Astron. & Astrophysics Encycl. 178/2 The aurora or the polar light is a magnificent, colorful, heavenly display that rewards those who defy the long and dark polar nights. Polar medal n. (in the United Kingdom and Commonwealth countries) a decoration awarded for distinguished service (now of at least ten years) to those exploring and working in polar regions, instituted by Edward VII in 1904 to acknowledge the return of Scott's first expedition to the Antarctic. ΚΠ 1904 Times 12 Sept. 8/2 (heading) New Polar medal... His Majesty the King has been graciously pleased to direct that a new medal for service in the Polar regions shall be struck. 1945 Geogr. Jrnl. 106 197 I have had to advise the Board on the question of the award of the Polar Medal. 1998 Guardian 14 July i. 18/4 The contribution to radar development by research on the ionosphere, coupled with glaciological discoveries and survey, earned each member of our team the Polar medal. polar nucleus n. Botany (in angiosperm reproduction) either of the two haploid nuclei which move from the poles of the embryo sac to the centre and fuse with the male gamete to form the triploid primary endosperm nucleus. ΚΠ 1882 S. H. Vines in tr. F. G. J. von Sachs Text-bk. Bot. (ed. 2) 581 In some instances the two polar nuclei meet, not in the centre, but towards the upper end of the embryo-sac. 1945 Q. Rev. Biol. 20 246/1 It was at first supposed that suppression of meiosis, or parthenogamy from a polar nucleus, might cause their appearance. 1992 M. Ingrouille Diversity & Evol. Land Plants 122 A double fertilization occurs with the formation of a diploid zygote (sperm nucleus plus egg) and a triploid endosperm nucleus (male gamete plus two polar nuclei). polar orbit n. an orbit of a spacecraft or satellite that passes over the polar regions of a celestial object; spec. one whose plane contains the polar axis. ΘΚΠ society > travel > air or space travel > space flight > [noun] > a space shot or flight > course or trajectory of spacecraft > orbiting > types of orbit parking orbit1941 polar orbit1956 transfer orbit1961 Molniya orbit1981 1956 Sci. Monthly July 16/1 In the polar orbit, however, the rotation of the earth causes the track of the satellite over the ground to spiral around in a complicated fashion. 1961 Times Rev. Industry Feb. 26/3 There are a number of possible satellite systems using polar, inclined and equatorial orbits. 1995 Denver Post 27 May c1/5 The agency maintains four satellites (two in polar orbit and one in ‘geostationary’ position over each coast). polar-orbiting adj. that moves in a polar orbit. ΚΠ 1958 Appeal-Democrat (Marysville–Yuba City, Calif.) 31 Dec. 5/7 The first Polar-orbiting satellite. 1963 Science 4 Jan. 36/1 There are two members of the OGO family: EGO (Eccentric Geophysical Observatory) and POGO (Polar Orbiting Geophysical Observatory). 1994 GPS World Apr. 22/2 Instruments used by ARGOS to determine buoy positions and to telemeter their data are carried on two polar-orbiting NOAA satellites. polar plant n. the compass plant, Silphium laciniatum (family Asteraceae ( Compositae)), a tall, deep-rooted North American plant bearing large flowers similar to sunflowers and leaves that face north and south. ΘΚΠ the world > plants > particular plants > plants and herbs > according to family > Compositae (composite plants) > [noun] > compass-plant or silphium silphium1771 turpentine weed1819 rosinweed1831 resinweed1838 polar plant1842 compass-flower1847 compass-plant1848 cup-plant1848 pilot weed1848 turpentine shrub- 1842 Farmer's Cabinet 15 Nov. 111/2 At mid-day, the plane of the Polar plant passes through the sun, and thus it shuns the light. 1963 Lima (Ohio) News 26 Apr. 15/2 The tall, erect leaves of the Silphium laciniatum (compass plant, pilot weed, polar plant, rosin weed) stand nearly vertical. 1996 Chiltern Seeds Catal. 219 Compass Plant, Pilot Weed, Polar Plant. The most famous plant from the American Prairies, this is an aristocratic species growing to 6 ft. or more. polar projection n. a projection of the earth's surface or of the celestial sphere on to a plane in which the centre of projection is one of the poles. ΚΠ 1625 N. Carpenter Geogr. Delineated i. vii. 182 (Polar projection) This kinde of proiection, though more vnusuall,..wants not his speciall vse in describing the parts of the earth neare the Pole. 1717 J. Green Constr. Maps & Globes i. iv. 22 The Stereographick Projection of the Sphere upon the Plane of the Equator, commonly call'd the Polar Projection. 1866 Jrnl. Royal Geogr. Soc. 10 221 Among them a chart of the southern hemisphere on the Polar Projection, illustrative of the ice-drift during the different seasons. 1960 Times 16 Nov. 13/6 The light-blue flag of the United Nations with its polar projection of the world in white. 2003 National Art Coll. Fund Rev. 2002 119/1 In the arch above is a celestial planisphere, engraved with a polar projection of most of the known fixed stars. polar reciprocal n. a curve such that the polar of each point with respect to a given conic is tangential to another curve; (also) a polygon such that the polar of each point is a side of another given polygon; cf. sense reciprocal adj. 7a(b).Used analogously in spaces of higher dimension. ΚΠ 1845 Cambr. Math. Jrnl. 4 127 Two cones may be drawn, and the vertices of these lie in the line which is the polar reciprocal of the line of intersection of the two planes. 1885 C. Leudesdorf tr. L. Cremona Elements Projective Geom. 240 Two curves..such that each is the locus of the poles of the tangents of the other, and at the same time also the envelope of the polars of the points of the other, are said to be polar reciprocals one of the other with respect to the auxiliary conic. 1940 Amer. Math. Monthly 47 243 Since OK·OX is constant, the envelope of w´ is the polar reciprocal of the locus of X. 1995 Mathematica Pannonica 6 77 (title) On the area sum of a convex polygon and its polar reciprocal. 2006 Wave Motion 43 288 Another surface, called the wave surface, is the polar reciprocal of the slowness surface. polar surface n. Geometry a surface related to a given surface and a given point in a way analogous to the way a polar ( A. 2a) is related to a curve. ΚΠ 1865 Philos. Trans. (Royal Soc.) 155 761 With regard to this ellipsoid the wave-surface is its own polar surface, i.e. the polar plane of any point of the surface touches it in another point. 1950 Proc. Amer. Math. Soc. 1 328 In the elliptic case it is interesting to consider the polar surface Sⁿ⁻¹(π/2) to the given Sⁿ⁻¹. 1970 Ann. Math. 92 371 The distance on S³ from η(a, 0) to η(b, 0), i.e., the distance between the corresponding points on the polar surface. polar vector n. Mathematics a vector which changes sign when the signs of all its components are changed; cf. axial vector at vector n. 2a. ΚΠ 1903 Nature 22 Oct. 610/1 This algebra..does not discriminate between ‘polar’ vectors, e.g. forces and ‘axial’ vectors, e.g. couples. 1968 M. S. Livingston Particle Physics v. 101 Angular momentum is an axial vector quantity, unlike linear momentum which is a polar vector. polar wander n. Geology = polar wandering n. ΘΚΠ the world > the earth > geodetic references > [noun] > pole > axis > movement nutation1703 pendulation1908 polar wandering1909 polar wander1957 1957 Philos. Trans. (Royal Soc.) A. 250 142 The rate of polar wander is very small compared with the average frequency of reversal of the geomagnetic field. 2001 A. G. Smith in R. Riding & A. Yu. Zhuravlev Ecol. Cambrian Radiation ii. 19 Some fundamental change in the behavior of the earth for this period, e.g...large components of ‘true’ polar wander, or a marked change in obliquity or climate. polar wandering n. Geology the slow, erratic movement of the earth's poles relative to the continents which is thought to have occurred throughout geological time and is ascribed largely to continental drift; (in extended use) a corresponding movement on other planets. ΘΚΠ the world > the universe > planet > [noun] > part of planet > polar wandering polar wandering1909 the world > the earth > geodetic references > [noun] > pole > axis > movement nutation1703 pendulation1908 polar wandering1909 polar wander1957 1909 Proc. Royal Soc. A. 82 90 ‘We need not wonder’ that the amplitudes of the polar wanderings ‘should often vary by 5 or 10 metres in the course of a few weeks or months.’ 1924 J. G. A. Skerl tr. A. Wegener Orig. Continents & Oceans viii. 123 Extensive, even if slow, polar wanderings are then able to take place. 1973 Science 9 Mar. 997 Polar wandering during the past 10⁸ years may be recorded by unique quasi-circular structures in the polar regions of Mars. 1985 Cambr. Encycl. Life Sci. xii. 307/1 These ‘polar wandering curves’ are different for each continent, which confirms that the continents have actually moved relative to one another. This entry has been updated (OED Third Edition, September 2006; most recently modified version published online March 2022). < adj.n.1556
随便看	accentuations accentuator accenty accept accept a person at her word accept a person at his word accept at a rebound accept at rebound accept at the rebound accept in worth accept persons accept service accept the face of accept the files accept the light accept the person of acceptabilities acceptability acceptable acceptableness acceptablenesses acceptably acceptance acceptance bank acceptance credit