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eccentric, a. and n.|ɛkˈsɛntrɪk|
Forms: 6 eccentrike, 6–9 excentric(k(e, 7–8 eccentrick, 7 ec-, excentrique, 7– eccentric.
[ad. late L. eccentricus, f. Gr. ἔκκεντρος eccentric as opposed to concentric (f. ἐκ out of + κέντρον centre); see -ic; the word is found in all the Romanic langs.: Fr. excentrique (14th c. in Littré), Pr. excentric, It. eccentrico, Sp. excéntrico.]
A. adj.
1. Of a circle: Not concentric with another circle (const. to). Of two or more circles: Not mutually concentric. Chiefly used of circles of which one is within the other. † eccentric orb: in the Ptolemaic astronomy, an orbit not having the earth precisely in its centre (afterwards sometimes used in a Copernican sense: an orbit not having the sun precisely in its centre).
1551Recorde Cast. Knowl. (1556) 247 These two circles..are eccentrike, for that they haue not one common centre. 1621Burton Anat. Mel. ii. ii. iii. (1651) 159/2 Which howsoever Ptolemy, &c., maintaine to be reall Orbs, excentrick, concentricke. 1656tr. Hobbes' Elem. Philos. (1839) 431 This annual orb [of the earth] is eccentric to the sun.
†b. fig. Not agreeing, having little in common. Const. from, to. Obs.
1607–12Bacon Wisdom, Ess. (Arb.) 184 His owne endes, which must needes be often eccentrique to the endes of his Master or State. 1666Collins in Rigaud Corr. Sci. Men (1841) II. 463 My book of Accounts..is so eccentric to your studies as I thought it unworthy your acceptance. 1670Sanderson in Ussher Power Princes (1683) Pref., A task..altogether excentrick from their function and calling.
2. That has its axis, its point of support, etc., otherwise than centrally placed. Cf. B. 2.
1647Ward Simp. Cobler 45 Else the world will be Eccentrick, and then it will whirle. 1743Savery in Phil. Trans. XLVIII. 177 Large object-glasses for telescopes are not commonly well center'd..I..return'd [two faulty ones] and had two sent me again, as eccentric well nigh as the former ones. 1825Wood Railroads 148 This eccentric circle is loose upon the axle..a circular hoop.. fits the circumference of the eccentric motion. 1831J. Holland Manuf. Metals I. 92 That ingenious but simple contrivance the eccentric wheel.
3. Not centrally placed. Of an axis, etc.: Not passing through the centre.
1849Sir J. Herschel Outlines Astron. iii. §141 (1858) 83 If the axis be excentric. 1882Vines Sachs' Bot. 203 The organic centre of the transverse section does not usually coincide with the geometrical centre, as is easily seen in the transverse sections of most petioles and horizontal branches with an ‘eccentric’ pith. 1884Bower & Scott De Bary's Phaner. & Ferns 365 The position of the bundle in the root is from the first slightly eccentric.
†b. Of a locality: Remote from the centre; out of the way. [So Fr. quartier excentrique.] Obs.
1800T. Jefferson Writ. (1859) IV. 312 [The College] is..eccentric in its position, exposed to all bilious diseases abandoned by the public care.
c. Phys. (See quot.)
1876Bernstein Five Senses 20 The sensation of sight can only take place..in the brain..and yet we transfer the object seen to the external world surrounding us. This fact is called the law of eccentric sensation.
†4. Misused for: Having no centre. Obs.
1633T. Adams Exp. 2 Peter iii. 7 Only that is eccentric, which was never made. 1652Benlowes Theoph. ii. xli. 28 Deaths hell deaths Self out-deaths, Vindictive Place!.. Excentrick Space! 1681tr. Willis' Rem. Med. Wks. Voc., Eccentric, without centre.
5. Of orbital motion: Not referable to a fixed centre of revolution; not circular. Of a curve, an elliptic, parabolic, or hyperbolic orbit: Deviating (in greater or less degree) from a circular form.
1642Howell For. Trav. 77 Let these Lights..be kept from irregular and eccentrique motions. 1692Bentley Boyle Lect. vii. 247 They could not acquire such Revolutions in Ellipses very little Eccentric. 1796Morse Amer. Geog. I. 32 Like other planets moving about the sun in very eccentric ellipses. 1866Sir J. Herschel Fam. Lect. Sc., Comets 104 A comet moves round the sun..in an immensely elongated, or as it is termed a very eccentric, ellipse.
b. transf. Of a heavenly body: Moving in an orbit deviating (more or less) from a circle.
a1721J. Keill Maupertuis Diss. (1734) 63 The Comets are no more..than very excentric Planets. a1791Wesley Serm. lxix. 8 Wks. 1811 IX. 249 Those horrid, eccentric orbs. 1816J. Smith Panorama Sc. & Art I. 581 When very eccentric planets or comets go round any flat star, in orbits much inclined to its equator.
c. eccentric anomaly: the true anomaly of a planet moving in an eccentric orbit (opposed to the mean anomaly). eccentric equation: see equation.
6. fig. Regulated by no central control.
a. Of actions, movements, and things in general: Irregular, anomalous, proceeding by no known method, capricious.
c1630Drummond of Hawthornden Poems 195 Finding all eccentrick in our times. 1792Burke Pres. St. Aff. Wks. I. 586 The eccentrick aberration of Charles the Second. 1848Macaulay Hist. Eng. I. 657 This eccentric clemency has perplexed some writers.
b. Of persons and personal attributes: Deviating from usual methods, odd, whimsical.
168586 Loyal Poems, Shaftesbury's Farew. 6 The brightest, yet the most excentrick Soul. 1695Ld. Preston Boeth. ii. 68 The Extravagance of Excentrick and irregular Desires. 1771Mackenzie Man Feel. xxxiv. (1803) 61 His motives were rather excentric. 1802M. Edgeworth Moral T. (1816) I. Pref. 7 [Forester is the picture of] an eccentric character. 1836H. Rogers J. Howe ii. (1863) 19 That great, though unequal and eccentric genius.
7. a. quasi-adv. b. absol. quasi-n.
1672Dryden Conq. Granada i. v. i, He moves excentrique, like a wand'ring Star. 1870Lowell Among my Bks. Ser. i. (1873) 203 Wordsworth never quite saw the distinction between the eccentric and the original.
B. n.
†1. [= eccentric circle, orb; see A. 1.] In Ptolemaic astronomy: A circle or orbit not having the earth precisely in its centre. Obs. exc. Hist.
[1398Trevisa Barth. De P.R. viii. xi. (1495) 317 The fyrste meuynge of a planete..is a cercle that hyghte Ecentricus.] 1561Eden Art Navig. i. xx. 22 Eccentricke, is a circle which hath his center distant..from the center of the worlde. 1646Sir T. Browne Pseud. Ep. 293 The Perigeum or lowest part of the eccentric. 1724Watts Logic (1736) 225 Excentricks and Epicycles of Ptolomy. 1783W. F. Martyn Geog. Mag. I. Introd. 14 A number of circles called eccentrics and epicycles.
fig.a1660Hammond Wks. IV. 551 Reserving..somewhat for common calamities, somewhat as it were for the universal motion of the whole body, somewhat for eccentricks.
2. Mech. A circular disc fixed on a revolving shaft, some distance out of centre, working freely in a ring (the eccentric strap), which is attached to a rod called an eccentric rod, by means of which the rotating motion of the shaft is converted into a backward-and-forward motion. Its most frequent use is for working the slide-valve of a steam-engine. (Earlier eccentric circle, motion; see A. 2).
1827Specif. Mandelay's Patent No. 5531 It consists..in the application of an eccentric to work the slide [valve]. 1838Public Wks. Gt. Brit. 69 The slides are worked by four fast eccentrics..instead of two loose ones. 1881Mechanic §657. 302 The set screw in the eccentric shall be downwards.
3. [Cf. A. 6 b.] A person whose conduct is irregular, odd, or whimsical.
1832Scott St. Ronan's Introd., Men of every country playing the eccentric. 1850Kingsley Alt. Locke vi. (1879) 65, I have given no description of the old eccentric's abode.
C. attrib. and Comb.
a. In various parts connected with the eccentric that works the slide-valve in a steam-engine, as eccentric-catch, eccentric-hook, eccentric-rod. Also eccentric-hoop, -ring, or -strap, the ring in which the eccentric revolves.
b. In various machines or parts of machines, whose distinctive feature is that they are worked by an eccentric wheel or depend upon an eccentric arrangement; as eccentric-arbor, eccentric-chuck, eccentric-cutter (in Turning), eccentric-engraving, eccentric-fan, eccentric-gear, eccentric-pump.
1859Handbk. Turning 57 Eccentric turning..includes all the various..work for which the powers of a lathe are..celebrated. Ibid. 87 Eccentric chuck. 1884F. J. Britten Watch & Clockm. 100 When the three screws are loosened the two parts of the eccentric arbor may be shifted. |