α. late Middle English–1800s filtre, 1500s fylter, 1500s fyltre, 1500s fylture, 1500s–1600s feltre, 1500s– filter.
β. 1600s philter, 1600s–1700s philtre.
filtern.
/ˈfɪltə/, U.S. /ˈfɪltər/ΘΚΠ
the world > textiles and clothing > textiles > textile fabric or an article of textile fabric > textile fabric > textile fabric made from specific material > made from mixed fibres > [noun] > wool and hair or fur > piece of
filter?a1425
felt1527
?a1425 Mandeville's Trav. (Egerton) (1889) 152 Þai dwell all in tentez made of blakk filtre.
?a1425 Mandeville's Trav. (Egerton) (1889) 125 Þan es he sette apon a blak filtre, with þe whilk þai lift him vppe and settez him in his trone.
2.
a. A strip or thread of felt, cloth, or other absorbent material, through which liquid is drawn by capillary action and collected in a separate vessel, thus freeing it of any suspended matter. Cf. felt n.1 2a. Now only in capillary filter n. at capillary adj. and n. Compounds.The sense in quots. ?a1425 and 1544 is ambiguous; they may instead belong at sense 2b.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator > drip
filter?a1425
list1593
?a1425 tr. Guy de Chauliac Grande Chirurgie (N.Y. Acad. Med.) f. 125 (MED) Lac virginis..þat is made of litarge & tempred wiþ white acete distilled with a filtre [?c1425 Paris by filtre; L. cum filtro].
1544 T. Phaer tr. J. Goeurot Regiment of Lyfe (new ed.) ii. f. xi Take .iii, ounces of litarge of siluer fyne poudred, halfe a pynte of good whyte vinegre, mixt them togyther, & distylle them by a fyltre, or throughe a lytle bagge or by a pece of cloth.
1559 P. Morwyng tr. C. Gesner Treasure of Euonymus 75 Destillacion by a Filter [L. per filtrum] or a list of Wollen cloth.
1576 G. Baker tr. C. Gesner Newe Jewell of Health iv. f. 232v By the beake or nose of the Lymbecke, with a thread draw the Fyltre of a finger breadth cut, so highe vp, that for the strayghtnes of the Nose, the Fyltre wyll no further followe.
1644 K. Digby Two Treat. i. xix. 167 When these partes of water are gott vp to the toppe of the vessell on which the filter hangeth, and ouer it on the other side by sticking still to the towe,..they fall downe againe by little and little.
1728 E. Chambers Cycl. at Filtre Filtres are of two sorts... The second are twisted up like a Skain or Wick... By means hereof, the purest Part of the Liquor distills Drop by Drop out of the vessel.
1746 H. Pemberton in tr. Dispensatory Royal Coll. Physicians 161 The filtre here meant is a twist of linnen thread or cotton laid over the edge of the vessel, one end touching the liquor within, and the other hanging without.
b. A thin piece (or esp. in early use a bag) of felt, cloth, mesh, or other porous material (now typically unsized paper) through which liquid is passed to free it of suspended matter. Cf. felt n.1 2a.bag-filter, membrane filter: see the first element.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator > cloth or bag
strainer-cloth1444
hippocras bag?a1500
felt1527
filter1576
Hippocrates' bag1605
Hippocrates' sleeve1605
manica Hippocratis1651
hippocras sleeve1679
bag-filtera1877
1576 G. Baker tr. C. Gesner Newe Jewell of Health i. f. 21 This is a Bagge which the Chimistes make of whyte Woollen cloth..shaped and sowen after this manner, and name it a Fylter.
1612 B. Jonson Alchemist ii. iii. sig. D4 Sir please you Shall I not change the feltre ? View more context for this quotation
1683 J. Pettus tr. L. Ercker ii. xlv. 214 in Fleta Minor i Dissolve the Vitriol, and purify it through a Filtre.
1770 T. Lane in Philos. Trans. 1769 (Royal Soc.) 59 220 The clear liquor being decanted, the remainder was passed through a filter.
1812 H. Davy Elements Chem. Philos. 285 The whole is then to be poured upon a filtre of cloth.
1846 J. Baxter Libr. Pract. Agric. (ed. 4) I. 53 Collected on a filter, washed and dried.
1900 Artist Jan. 72/1 Collect the deposit on a filter and dry it in an oven or before a fire.
1949 Our Industry (Anglo-Iranian Oil Co.) (ed. 2) xiii. 291 Cases where the oil has to pass through an unheated filter of very fine mesh where suspended solid wax crystals would be liable to collect on the filtering surface and retard the rate of filtration.
1956 Limnol. & Oceanogr. 1 203/1 Particulate matter in the water samples was separated on millipore filters.
2015 Dayton (Ohio) Daily News (Nexis) 6 May d3 Use two paper filters, fitted together, each time you brew a pot of coffee. The strength of two keeps them from collapsing.
c. More widely: any of various devices or other methods used to remove suspended or dissolved impurities from liquid; esp. a vessel in which liquid passes through a layer of sand, charcoal, mesh, or some other porous material.charcoal filter, percolating filter, water filter, etc.: see the first element.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator
filterer1788
filter1791
percolator1842
1791 J. Peacock Brit. Patent 1844 The filters will be cleansed by .
1834 Brit. Patent 6708 An improved filter for water or other liquids.
1867 S. W. Baker Nile Tributaries Abyssinia xx. 502 Nevertheless the natives had scraped small holes in the sand, as filters.
1911 Times Engin. Suppl. 22 Mar. 27/4 Sand filters had been used in Britain since about 1829.
1953 R. W. Fairbrother Text-bk. Bacteriol. (ed. 7) vi. 67 After use the components of the filter should be sterilized and cleaned.
2010 J. W. Whitehead Appraising Graduate ii. v. 76 The lulling sound of the water filter burbles just off-screen.
d. Any material suitable for use as a filter.
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the world > matter > chemistry > equipment or apparatus > [noun] > miscellaneous apparatus
bain1477
speculum1650
filtering paper1651
wheel-fire1662
filter paper1670
sun furnace1763
respirator1789
candle-ball1794
rectifier1822
candle-bomb1823
filter1823
oxyhydrogen blowpipe1823
shade1837
graduator1839
pipette1839
thistle funnel1849
pressure tube1852
ozonizer1858
dialyser1861
Liebig condenser1861
Sprengel pump1866
Sprengel tube1866
water softener1867
mercury pump1869
Bunsen burner1870
dialysator1877
test-mixer1877
tube-condenser1877
Kipp1879
reflux condenser1880
policeman1888
converter1889
pressure boiler1891
spot plate1896
hydrogen electrode1898
sampler1902
reactor1903
fume-chamber1905
Permutit1910
microburner1911
salt bridge1915
precipitator1919
Raschig ring1920
microneedle1921
titrator1928
laboratory coatc1936
spray tower1937
precipitron1938
ion exchanger1941
potentiostat1942
chemostat1950
Knudsen pipette1951
pH-stat1956
cryopump1958
the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > material used for filtering
cap-paper1634
filter1823
1823 J. Badcock Domest. Amusem. 26 The burning it [sc. charcoal] over and over again..produces a better filtre than at first.
1870 Nature 27 Jan. 341/2 This [sc. cotton-wool] was the filter used by Schrœder in his experiments on spontaneous generation.
1909 W. S. C. Russell & H. C. Kelly Lab. Man. First Year Sci. 31 (heading) Charcoal as a filter.
1987 Res. & Devel. in Agric. 4 109/2 Gravel was recommended as an excellent filter, if available.
2009 J. Soukhome et al. Watershed Investig. xii. 155 Sand is not only a good filter but also is porous and allows water to filter through quickly.
e. A device or other method used to remove smoke, dust, germs, or other impurities from the air.air filter: see air n.1 Compounds 2.
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1825 London Jrnl. Arts & Sci. 10 153 The wetted sponge acts as a filter, separating and taking up the deleterious matters, and allowing the pure air to pass to the lungs.
a1884 E. H. Knight Pract. Dict. Mech. Suppl. 15/2 A protective ventilator consisting of a cloth interwoven with thin brass wire to act as a filter for the air.
1937 Amer. Home Apr. 62/1 (advt.) Billions of infinitesimal germ-laden particles, present in air that has not been cleaned, are caught and held by these filters at the air-intake.
1957 I. Asimov Naked Sun ii. 22 With filters in his nose to keep out germs, and gloves on his hands to prevent contact.
1986 Photographer May 30/2 (advt.) The..system circulates warm air through the purifying filter to remove any dust particles.
2008 Vancouver Province (Nexis) 11 Apr. c14 Aftermarket filters deliver cooler, clean air needed for extended engine life, better fuel economy and additional power.
3. figurative and in extended use. Anything which serves as a selectively permeable barrier, through which only some things may pass.
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1605 T. Tymme tr. J. Du Chesne Pract. Chymicall & Hermeticall Physicke i. v. sig. D2v The common salte..passing through the philter of the earth [L. filtro terrae].
1672 N. Grew Anat. Veg. i. 21 A Filtre to the transient Sap.
1780 Monthly Rev. 61 534 A secondary nature, which they [sc. the matters which are converted into calxes] have contracted, by passing through filters in which they have degenerated from their original character.
1802 W. Paley Nat. Theol. xii. 241 This natural filter [sc. the bill of a duck].
1873 H. B. Tristram Land of Moab xii. 228 A heavy conversation of ponderous compliments passed through the dragoman filter.
1911 A. Mitchell tr. H. Bergson Creative Evol. iv. 356 The universe..can only be a system of laws if phenomena have passed beforehand through the filter of an intellect.
1990 Psychol. Rep. 66 iii. 2 After impulses have been generated in the mind..they encounter a variety of filters which determine whether the impulse is acted upon.
2011 J. Gleick Information xv. 410 The harassed consumer of information turns to filters to separate the metal from the dross; filters include blogs.
4.
a. A cylindrical pad of absorbent material fitted at the mouth end of a manufactured cigarette, or placed in the end of a hand-rolled cigarette, in order to reduce harmful ingredients in the inhaled smoke. Also: a manufactured cigarette fitted with such a pad.Quot. 1851 shows a use of sense 2e in the context of removing some substances from the smoke inhaled from a type of modified cigar.
ΘΚΠ
the world > physical sensation > use of drugs and poison > tobacco > smoking > articles or materials used in smoking > [noun] > thing which may be smoked > cigarette > filter
filter1870
filter tip1932
the world > physical sensation > use of drugs and poison > tobacco > smoking > articles or materials used in smoking > [noun] > thing which may be smoked > cigarette > other types of cigarette
Russian cigarette1851
papirosa1856
Egyptian1892
Russian1892
tickler1904
joystick1911
gyppy1920
king-size1920
Sobranie1923
virgin1923
Turk1926
roll-your-own1932
ready roll1949
roll-up1950
filter1956
filterless1956
rollie1964
Virginia1964
untipped1968
primo1986
1851 Morning Chron. 12 Aug. 6/2 A prepared medium in the mouth piece of the cigarilla, which, acting as a filter, absorbs all the empyreumatic oil.]
1870 Patents for Inventions: Abridgm. Specif. Tobacco 139 Such a filter may be included in the manufacture of a cigar or cigarette by rolling it up in the outer wrapper.
1908 Lancet 21 Mar. 907/2 A large proportion of the objectionable oils formed during smoking is arrested in the wool filter.
1956 Ada (Okla.) Evening News 4 Jan. 4/2 Everybody rides like mad in automobiles or flies, plays golf, shoots craps, ruins their eyes on television, smokes filters and drinks vodka.
1994 Irish Times 15 Han. 15/5 I insert a filter at the end of my cigarettes as I roll them.
2011 Charleston (W. Va) Gaz. (Nexis) 1 May 1 f If you smoked a filter, you switched to a nonfilter.
b. Photography. A device placed over the lens of a camera to absorb light of certain wavelengths or polarities.Recorded earliest in light filter n. at light n.1 Compounds 3.colour filter, light filter, sky filter, etc.: see the first element.
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society > leisure > the arts > visual arts > photography > camera > parts and accessories of camera > [noun] > lens > filters
filter1874
light filter1874
colour screen1884
colour filter1891
mosaic screen1908
mosaic1911
sky filter1915
polarizer1935
polarizing filter1939
skylight filter1950
1874 Brit. Jrnl. Photogr. 7 Aug. 375/2 The other two kinds of light filters he uses require to be worked with full, or almost full, apertures.
1958 Newnes Compl. Amateur Photogr. viii. 97 Light filters are transparent, coloured discs which are attached to the camera lens for the purpose of modifying the colour quality of the light transmitted.
2001 Outdoor Photographer Aug. 87/1 When polarizers are used with a wide-angle lens..the thickness of the filter will cause vignetting.
c. Radiology and Nuclear Physics. An object or device that is placed in the path of a beam of X-rays, particles, etc., in order to absorb components of specific wavelengths or energies.
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the world > matter > physics > atomic nucleus > radioactivity > [noun] > material reducing intensity of radiation
filter1903
the world > health and disease > healing > medical treatment > treatment by radiation > [noun] > by X-rays > filter or screen
screenage1916
filter2006
the world > matter > physics > atomic nucleus > radioactivity > X-rays > [noun] > material reducing intensity of
filter2006
1903 Electr. Rev. 12 Dec. 849/2 Selective filters should be employed to strain out undesirable radiations.
1969 G. E. Bacon Neutron Physics x. 127 We can..use a sufficiently thick block of graphite as a filter which..removes all neutrons with a wavelength greater than 0·67 nm.
2006 Washington Post (Nexis) 15 May d5 MXF Technologies has developed tunable monochromatic X-ray filters that can be attached to a standard X-ray tube.
d. Electronics. A passive circuit that attenuates all signals except those of specific frequencies.Recorded earliest in wave filter n. at wave n. Compounds 2.comb filter, band-pass filter, notch filter, etc.: see the first element. See also high-pass adj. at high adj. and n.2 Compounds 4, low-pass adj. at low adj. and n.2 Compounds 3.
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the world > matter > physics > electromagnetic radiation > electronics > electronic devices or components > [noun] > filter
filter1908
filter circuit1912
the world > matter > physics > electromagnetic radiation > electronics > electronic phenomena > electronic circuit > [noun] > filters
filter1908
wave filter1908
prototype1923
slope circuit1966
1908 London, Edinb. & Dublin Philos. Mag. 6th Ser. 16 481 This machine has been used with a wave filter, consisting of series inductances of low effective resistance and parallel capacities.
1923 Harmsworth's Wireless Encycl. 933 A filter is generally employed with high-frequency amplifiers for preventing signals from other stations than the one sought being amplified.
1955 G. M. Glasford Fund. Television Engin. xvii. 581 There must be employed in the video section a 4·5-Mc rejection filter to remove the audio carrier and its sidebands from the video signal.
2004 Keyboard Feb. 51/1 (advt.) More than 50 new synth-engine parameters including multi-mode filters, envelopes, LFOs and more.
2015 A. Hemami Electr. & Electronics for Renewable Energy Technol. xvi. 488 This variation of the voltage level, called a ripple, can be smoothed out to some extent by employing a filter.
e. Computing. A program or software function that removes or hides certain emails, web pages, search results, etc., according to preset rules or conditions. Frequently with distinguishing word, as parental filter, search filter, spam filter, etc.
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1986 T. Malone et al. Intelligent Information Sharing Syst. 26 Would employees..want their supervisors to know that they had filters selecting notices about job opportunities in other parts of the company?
1994 InfoWorld 31 Oct. 138/2 Mail filters are only useful in any E-mail system if you are getting lots of E-mail, at least a dozen messages a day.
2000 Today's Parent Oct. 142/2 Some search engines, including Excite, let you turn on a family ‘filter’ that blocks known porn sites.
2005 Computer Weekly 19 Apr. 54/1 The risk that legitimate e-mail may be mistakenly blocked by a spam filter..has given many companies sleepless nights.
2013 Times (Nexis) 13 July 62 You can use the site to search for advisers in your area and can set filters to find specialists who have higher-level qualifications.
5. Chiefly British and Irish English. In a road traffic system: an arrangement allowing or directing vehicles to turn right or left at an intersection or other junction, typically independently from the flow of traffic going straight ahead; a lane for this purpose. Also: a traffic light signalling this, usually displaying an illuminated green arrow. Cf. filter v. 3c.Recorded earliest in filter light: see Compounds 1b.
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1939 Irish Times 5 Aug. 6/1 Filter lights, to permit traffic to make left turns at some of the light-controlled crossings in Dublin while the normal cross-traffic is held up.
1955 Hansard Commons 22 Mar. 1870 In reply to a Question which I asked last week about the filter, he said that he was advised that it was bad for traffic, but can he say how a filter to the left can possibly be bad for traffic?
1987 Guardian 23 Feb. 20/8 Rather than the signal disappearing to show that the filter had ended and oncoming traffic could be expected, the green became ‘solid’.
1995 A. Warner Morvern Callar (1996) 56 Beyond the north pier I got up into fourth and did forty then changed down smoothly at the filter by the Gathering Halls.
6.
a. A program or (now usually) software feature used to alter the overall appearance of a digital image in a specific manner. Cf. senses 4b, 4d.
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1965 Space Programs Summary: Supporting Res. & Adv. Devel. No. 37-31. iii. 26/1 Two-dimensional digital filters were programmed which determined the magnitude of the unwanted frequency at each point in the picture and then subtracted these noises out.
1982 Proc. 8th Triennial World Congr. Internat. Federation of Automatic Control 1981 I. 271/2 The proposed two-dimensional digital filters can be applied to the restoration of blurred images.
1991 Infoworld 6 May 48/2 Aldus Gallery Effects, Volume I: Classic Art comes with 16 artistic filters, including chalk and charcoal, watercolor, fresco, chrome, graphic pen, and film grain.
2000 G. L'E. Turner Elizabethan Instrument Makers ii. 290 The best technique for this is the Unsharp Mask filter in Photoshop. Unsharp Masking is the traditional film compositing technique used to sharpen edges in an image.
2015 Buffalo (N.Y.) News (Nexis) 14 Sept. d41 Instagram's two dozen filters..adjust for brightness, contrast, saturation and ‘warmth’.
b. Computing. A program or software function that processes data, and orders or reformats it according to some preset rule or condition.
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1966 C. J. Sippl Computer Dict. & Handbk. 128/1 Filter,..2. A device or program that separates data, signal, or material in accordance with specified criteria.
1981 Arrl Bull. in net.ham-radio 13 Nov. I run the bulletins through a filter to convert everything to lower case.
2001 D. Pountain New Penguin Dict. of Computing 185/2 Filter, in general a program that inputs a set of data items, performs some operation on each item, and outputs the modified results.
2013 M. G. Sobell Pract. Guide Linux Commands, Editors, & Shell Programming (ed. 3) v. 126 This chapter also explains how to redirect input to and output from a command, construct pipelines and filters on the command line, and run a command in the background.
Compounds
C1.
a. General attributive and appositive.Recorded earliest in filter bag n. at Compounds 2.
ΚΠ
1559 P. Morwyng tr. C. Gesner Treasure of Euonymus 395 At length strain it oft through a Filter bag.
1842 C. Dickens Amer. Notes II. iv. 112 I have seen water like it at the Filter-shops.
1891 Jrnl. Soc. Chem. Industry 31 July 650/2 These oxides are..taken up by the filter-fabric and act as mordants.
1922 Mech. Engin. Sept. 126/2 The ring constituting the filter housing is placed well away from the fan wheel.
1951 R. E. Kirk & D. F. Othmer Encycl. Chem. Technol. VI. 516 The sand acts as the filter medium.
1967 Ann. Occup. Hygiene 10 77 3-in.-long nozzles were attached to the filter holder to allow isokinetic flow into the inlet.
2004 New Yorker 31 May 74/2 The beard of algae that hung from the filter device.
b. In sense 5, as filter arrow, filter lane, filter light, etc.
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society > travel > transport > transport or conveyance in a vehicle > vehicular traffic > [noun] > traffic control > traffic lights > specific
red light1790
green arrow1875
amber light1896
yellow1900
yellow light1920
amber1929
stop light1930
stop sign1934
filter1939
red1940
green1962
1939Filter lights [see sense 5].
1952 Irish Times 17 Oct. 4/2 For traffic coming up Pearse street toward D'Olier street, the traffic lights often present a green filter arrow allowing them to proceed when traffic bound for Tara street is halted.
1971 ‘K. Royce’ Concrete Boot x. 120 Reaching the filter lane for Watford I had to make up my mind whether to take it or carry straight on on the Oxford Road.
2004 Independent 20 Sept. (Review section) 5/1 A steady stream of traffic,..shops, filter-lanes, clutches of greenery—scenes so ordinary that they seem to haze into a kind of virtual townscape.
C2.
filter aid n. any of various powders used to increase the porosity of a filter cake and prevent it from blocking the filter.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter aid
filter aid1914
1914 Jrnl. Industr. & Engin. Chem. 6 145/2 A series of experiments was undertaken, adding various ‘filter aids’ to the fluid.
1951 R. E. Kirk & D. F. Othmer Encycl. Chem. Technol. VI. 510 Materials such as kieselguhr or diatomite, asbestos fibres,..and sawdust flour are examples of materials used as filter aids.
2003 Jrnl. Amer. Water Wks. Assoc. 95 128/2 Cationic polymer is added as a filter aid.
filter bag n. (a) a bag used as a filter; (b) Photography a coloured bag placed over a light source in order to change its colour.
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1559Filter bag [see Compounds 1a].
1676 R. B. Brief Acct. Choice & Famous Medicines 17 Let it run through a Flannel Cloth, or Filter Bag.
1851 Mechanics' Mag. 29 Nov. 436/2 The matters left in the filter bags are to be treated as before described.
1946 Brit. Jrnl. Photogr. 22 Nov. 424/3 (advt.) Special Infra-red or Violet Flexible Filter Bag for flashlight effects and scientific work.
1969 Focal Encycl. Photogr. (rev. ed.) 609/1 Special deep red or almost opaque filter bags have also been used for infra-red photography.
2012 N. Queensland Reg. (Nexis) 1 Mar. 14 Any deposits dislodged from the pipes are captured in a filter bag at the end flush site.
filter bank n. Electronics an array of filters (sense 4d) used to separate an input signal into multiple frequency sub-bands; a device incorporating such an array.
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1938 L. R. Wrathall U.S. Patent 2,117,752 (caption) Even harmonic filter bank.
1971 J. M. Sutton et al. in R. D. Davies & F. G. Smith Crab Nebula ii. v. 97 The sensitivity can be considerably improved by tracking the pulses as they sweep in frequency using individual channels of a filter bank to track different parts of the pulse.
2008 Time Out N.Y. 23 Aug. 71/3 My main piece is the Akai MPC 4000, which is a sampler and a sequencer, and then lots of effects stuff, like a filter bank and the Kaos Pad, and a drum machine and some other things.
filter bed n. a layer of sand, gravel, or other porous material serving as a filter; a pond or tank incorporating such a layer.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator > others
filter bed1828
physeter1842
sack-filter1875
biofilter1936
permeator1975
1828 London Lit. Gaz. 29 Nov. 763/2 A project said to be in contemplation by the company for cleansing the foul water, by means of excavations and filter-beds.
1881 Pop. Sci. Monthly June 283/2 The filter-bed, which may be composed of any suitable material, is contained in a closed cylinder.
1948 L. E. H. Whitby Nurses' Handbk. Hygiene (ed. 8) ii. 46 After storage the water is allowed to percolate slowly through a filter-bed.
2010 Observer 21 Mar. (Guide to Pets) 37/2 Carefully add the gravel to a depth of around 5cm... This acts as the filter bed.
filter cake n. the insoluble residue left on a filter following filtration.
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the world > physical sensation > cleanness and dirtiness > dirtiness > pollution or defilement > [noun] > specific impurities > filter cake
filter cake1861
1861 Jrnl. Soc. Arts 3 May 442/1 It [sc. the plate] will..be easily freed from its clogging matters, which cannot penetrate into it, the porosity of the filter-cake being too fine.
1912 Mining & Engin. World 20 Apr. 863/3 In forming a filter cake with any material there is a certain point where the rate of filtration begins to drop off very rapidly due to the resistance offered by the cake.
1967 Filtration & Separation 4 471 Most filter cakes show some degree of compressibility.
2000 Paper Technol. Feb. 31/2 Effluent is then pumped in to a plate-type filter press, which produces a filter cake with a dry solids content in excess of 50%.
filter-caked adj. rare that has become a filter cake.
ΘΚΠ
the world > physical sensation > cleanness and dirtiness > dirtiness > pollution or defilement > [adjective] > filter-caked
filter-caked1956
1956 K. Imhoff et al. Disposal of Sewage xii. 202 The filter-caked sludge may be dried finally by heat and sold as fertilizer.
1975 Steelworkers Arbitration Awards 19 896/2 For the next few years, the filter-caked sludge was sold to a contractor who converted it to sinter.
filter capacitor n. Electronics a capacitor used as an electronic filter, esp. as a component of a filter circuit.
ΚΠ
1927 Pop. Radio Jan. 95 (advt.) Reliability is essential to Satisfaction in By-Pass and Filter Capacitors.
1972 Pop. Mech. Jan. 44/2 The high-frequency alternating current emitted by a vacuum-cleaner motor could be enough to cause radio wave interference. For this reason, some vacuum cleaners are equipped with filter capacitors that suppress this high frequency.
2013 Irish Daily Mail (Nexis) 24 Apr. 42 The small current will slowly charge a filter capacitor inside the CFL [= compact fluorescent lamp] until it reaches a critical threshold, at which point the lamp will flash on momentarily.
filter cartridge n. a cartridge containing a filter, typically designed to be an easily replaced component of another device.
ΚΠ
1900 E. Landfried U.S. Patent 656,649 1/1 I..have invented certain new and useful Improvements in Filter-Cartridges for Tobacco-Pipes, Cigar-Holders, and the Like.
1948 Motorboating Mar. 130/2 Install a new filter cartridge and use solvent as directed to keep the motor clean and free from sludge.
2015 Irish Times (Nexis) 11 June (Property section) 2 When you use your tap, cold water is diverted through the filter cartridge, removing a wide range of possible contaminants including lead and other heavy metals.
filter cell n. (a) a compartment inside which liquid or gas is made to pass through a filter; (b) (also filter-cel) a type of diatomaceous earth, typically used as a flocculant or filter aid.In form Filter-Cel, a proprietary name in the United States. In form Filtercel, a proprietary name in the United Kingdom.
ΚΠ
1880 Amer. Machinist 18 Sept. 2/2 The admission is at the top of the filter cells instead of at the center.
1915 Sugar July 53/1 From Celite, a cellular highly siliceous mineral, is produced a material marketed under the name, ‘Filter-Cel’—a specially prepared chemically inert natural filtering medium of low density.
1953 Sewage & Industr. Wastes 25 1380/1 This technic uses a muslin cloth overlaid with Whatman No. 40 filter paper and a layer of filter cell.
2011 R. Caenn et al. Composition & Properties Drilling Fluids (ed. 6) iii. 120 A common and convenient form of apparatus consists of a modified filter cell,..and a disc or rod to simulate the drill pipe.
filter cigarette n. a filter-tipped cigarette.
ΚΠ
1938 Life 14 Feb. 5/2 (advt.) Smoke over a pack of cigarettes—then look at the filter cigarette.
1981 Times 25 July 3/8 Filter cigarettes were..assumed to be safer than those without tips.
2003 J. D. Mauseth Botany (ed. 3) vi. 156/2 Tobacco leaves contain between 0.6% and 9.0% nicotine, and an ordinary filter cigarette has 20 to 30 mg of the alkaloid.
filter circuit n. Electronics a passive circuit that attenuates all signals except those of specific frequencies; = sense 4d.
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the world > matter > physics > electromagnetic radiation > electronics > electronic devices or components > [noun] > filter
filter1908
filter circuit1912
1912 Jrnl. Inst. Electr. Engineers 49 348 It is generally necessary to keep one point on the second filter circuit connected to earth.
1962 A. Nisbett Technique Sound Studio iv. 82 Correction of a whole range of faults, such as noise, distortion, and unsatisfactory frequency response, is often attempted by means of filter circuits.
2000 P. Scherz Pract. Electronics for Inventors viii. 265 Two of the major categories of integrated filter circuits include the state-variable and switched-capacitor filters.
filter coffee n. (a) (a drink of) coffee prepared by allowing freshly boiled water to pass through a paper or mesh filter containing finely-ground roasted coffee beans; frequently and in earliest use attributive, as filter coffee machine, filter coffee maker, etc.; (b) ground coffee suitable for using with a filter.
ΚΠ
1875 Commissioners of Patents' Jrnl. 29 Jan. 213/1 Caron, Brothers and Sister, for ‘A filter coffee machine’.—Dated 12th June. 1874.
1924 W. H. Ukers Coffee Merchandising xviii. 236 (heading) Drip or Filter Coffee. The principle behind this method is the quick contact of water at full boiling point with coffee ground as fine as it is practicable to use it.
1925 Manch. Guardian 17 Sept. 6/6 A filter-coffee served all to oneself in a tiny percolator.
1926 Bridgeport (Connecticut) Telegram 25 Sept. 13/2 (advt.) The Filter Coffee Maker is the answer. A perfect way to make coffee.
1938 Times 4 Jan. 8/7 After heating the pot thoroughly put in the filter coffee in the quantity of one tablespoonful for the pot and one for each person.
1977 C. McCullough Thorn Birds vii. 526 She opened the refrigerator, reached for the cream jug, opened the freezer door and withdrew a can of filter coffee.
1991 Which? Dec. 675/2 If you want a long, hot cup of freshly-ground filter coffee..this report will tell you what to buy.
1998 Independent (Nexis) 12 Dec. 7 Siemens goes a step further, by enlisting FA Porsche to create its flash filter-coffee machine.
2002 M. Roffey August Frost 285 The waiter brought a basket of bread and butter and two white filter coffees.
filter coffee pot n. (a) a (typically ceramic) coffee pot, the upper part of which is equipped with a filter; (b) any jug or pot used in the preparation of filter coffee.
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1870 T. J. Hovell-Thurlow Trade Unions Abroad & Hints for Home Legislation ii. 78 A very complete collection of similar earthenware, porcelain, and glass was exhibited by the Brothers Sieberg, of Amsterdam..:—Tea-pots..Milk jugs..Filter coffee-pots [etc.].
1876 M. F. Henderson Pract. Cooking & Dinner Giving 77 He preferred decidedly the coffee made in the French filter coffee-pot... It is not boiled... But to be explicit, put the coffee in the filter. At the first boil of the water, pour one or two coffee-cupfuls of it on the coffee.
1917 Amer. Cookery 21 803 (advt.) Send for a trial can..of Barrington Hall..Coffee... For drip or filter coffee pots.
1980 S. Campbell Cooks' Tools 248/2 The filter coffee pot..works in exactly the same way but looks much nicer, as jug and filter are made of matching glazed earthenware.
2009 T. de Chalain Wolf's Paw ix. 223 Seeing the filter coffee pot was still half full on the stand, he poured himself a cup.
filter condenser n. Electronics (now rare) = filter capacitor n.
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the world > matter > physics > electromagnetic radiation > electronics > electronic devices or components > [noun] > filter > part of
filter condenser1920
filter reactor1922
1920 Radio Amateur News Apr. 536/3 The remote control relay is on the back of the panel together with the tuning helix and condenser,..and filter condensers for the plate current.
1951 S. Deutsch Theory & Design Television Receivers xii. 406 The size of the various filter condensers is determined by consideration of tolerable ripple.
2005 Aberdeen (S. Dakota) Amer. News (Nexis) 21 Nov. a6 Interference from household sources could be eliminated simply by attaching a $5 filter condenser to the radio receiver.
filter factor n. Photography a numerical measure of the darkness or density of an optical filter, equal to the ratio of the exposure required with it in place to that required when it is not in place; = factor n. 6d.
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society > leisure > the arts > visual arts > photography > action of taking photograph > technical factors > [noun] > filter factor or scale of exposure
exposure1839
time exposure1870
inertiac1886
latitude1889
factor1900
filter factor1904
inertia point1907
intermittency effect1907
Scheiner number1911
scale1920
1904 C. H. Hewitt Pract. Professional Photogr. II. xii. 82 We need only multiply our exposure by the light filter factor.
1958 Newnes Compl. Amateur Photogr. vii. 98 Filters reduce the light transmitted to form the image and require a compensating exposure increase; with certain very pale filters..this filter factor is..small enough to be ignored.
2002 G. Rand & D. Litschel Black & White Photogr. (ed. 2) ix. 184/2 The filter factor is taken care of because the light reading is made through the filter.
filter faucet n. North American a faucet incorporating a filter to remove impurities from water.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator > on tap
tap-hose14..
filter faucet1846
tap-whisk1854
1846 Sci. Amer. 27 Aug. (heading) House's filter-faucet.
1915 Pop. Mech. Mar. 32/3 (advt.) Perfected self-cleaning filter-faucetcombined.
1958 Amer. City July 65/1 The latest counter-type models come in stainless steel or vitreous enamel, are furnished with sprayhead, bubbler and glass filter faucet.
2012 Compl. Guide Home Plumbing (Black & Decker) (ed. 5) 125/1 The filter faucet comes with a jamb nut.
filter flask n. [after German Filtrierkolben (1865 or earlier)] Chemistry a conical flask with a short protruding tube on one side through which suction may be applied, typically used in vacuum filtration.
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1869 T. E. Thorpe tr. R. Bunsen in London, Edinb. & Dublin Philos. Mag. 4th Ser. 37 17 In order to employ the consequent difference in pressure..for the purpose of filtration, it is only necessary to connect the mouth of the upper bottle with the tube of the filter-flask [G. Filtrirkolben].
1964 P. J. Hills Small Scale Org. Prepar. i. 1 Small conical flasks are also useful as receivers in distillation, and side-arm conical flasks (filter flasks) are used in filtering operations.
2015 C. K. Zercher Org. Syntheses XII. 462 A 250-mL filter flask is equipped with a 5 cm porcelain funnel and filter paper. The paper is wetted with water (1–2 mL) and the product is isolated by vacuum filtration.
filter inductor n. Electronics an inductor used as an electronic filter, esp. as a component of a filter circuit.
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1927 Handbk. Radio Standards (National Electr. Manufacturers Assoc.) (ed. 3) 24/1 It shall be recommended practice to rate a filter inductor with its inductance in henries at a specified frequency, alternating voltage, and direct current.
1973 N.Y. Times 16 Sept. iii. 28/1 (advt.) Must be familiar with design of ferro-resonant transformers, filter inductors, high frequency power transformers.
2004 M. G. Simões & F. A. Farret Renewable Energy Syst. vii. 140 Intuitively, a bigger filter inductor stores more energy at a given current level than a smaller one.
filter paper n. [compare earlier filtering paper n. at filtering n. Compounds 2] unsized porous paper used to filter liquids; a piece of this.
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the world > matter > chemistry > equipment or apparatus > [noun] > miscellaneous apparatus
bain1477
speculum1650
filtering paper1651
wheel-fire1662
filter paper1670
sun furnace1763
respirator1789
candle-ball1794
rectifier1822
candle-bomb1823
filter1823
oxyhydrogen blowpipe1823
shade1837
graduator1839
pipette1839
thistle funnel1849
pressure tube1852
ozonizer1858
dialyser1861
Liebig condenser1861
Sprengel pump1866
Sprengel tube1866
water softener1867
mercury pump1869
Bunsen burner1870
dialysator1877
test-mixer1877
tube-condenser1877
Kipp1879
reflux condenser1880
policeman1888
converter1889
pressure boiler1891
spot plate1896
hydrogen electrode1898
sampler1902
reactor1903
fume-chamber1905
Permutit1910
microburner1911
salt bridge1915
precipitator1919
Raschig ring1920
microneedle1921
titrator1928
laboratory coatc1936
spray tower1937
precipitron1938
ion exchanger1941
potentiostat1942
chemostat1950
Knudsen pipette1951
pH-stat1956
cryopump1958
society > leisure > the arts > visual arts > photography > photographic processes > processing and printing equipment > [noun] > other processing or printing equipment
filter paper1670
buffer1854
fuming-box1874
squeegee1878
light trap1881
changing table1882
print-washer1889
washer1891
safe lamp1893
rectifier1921
apron1935
register board1967
1670 W. Simpson Hydrol. Ess. 154 I caused that which remained in the Retort to be filtred, and sav'd the Sediment in the Filter Paper.
1729 G. Smith Nature Fermentation Explain'd 35 Run the Liquor through the flannel Slieve, or filter Paper for use.
1830 Philos. Mag. 2nd Ser. 8 385 The residuum of charcoal and sulphur left on the double filter-paper being well dried by the heat of ordinary steam, is estimated as usual by the difference of weight of the inner and outer papers.
1950 Manch. Guardian 5 Sept. 5/4 It [sc. chromatography] is a simple technique for analysing a mixture by allowing a drop of it to soak through a filter paper or a column of some substance.
2010 New Yorker 20 Dec. 62/1 Hunters throughout the country now routinely carry filter paper.
filter-passer n. now historical a substance or organism capable of passing through a filter; spec. a filterable virus.
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the world > life > biology > organism > micro-organism > other micro-organisms > [noun]
aerobian1865
anaerobian1865
microzyme1870
mycetes1874
pathogen1880
zooxanthella1882
aerobe1883
anaerobe1883
zymad1885
pathogerm1897
phytoflagellate1902
filter-passer1906
aerophile1907
zymocytea1909
fermenter1918
phytopathogen1918
phytomonad1926
pleuropneumonia-like organism1935
phototroph1941
mycoplasma1955
prokaryote1963
mycoplasm1964
serovar1973
spiroplasma1973
prokaryon1975
ureaplasma1975
the world > life > biology > organism > micro-organism > virus > [noun] > types of
latent virus1750
influenza virus1880
poxvirus1891
filter-passer1906
mosaic virus1914
bacteriophage1921
herpes virus1925
Rous sarcoma virus1925
Rous virus1925
papillomavirus1935
poliovirus1939
Semliki Forest virus1944
actinophage1947
mycophage1947
mengovirus1949
tumour virus1950
Zika1952
mycobacteriophage1953
Sindbis virus1953
myxovirus1954
echovirus1955
RNA virus1955
adenovirus1956
SV1956
arborvirus1957
enterovirus1957
foamy virus1957
respiratory syncytial virus1957
polyoma1958
parainfluenza1959
reovirus1959
arbovirus1960
cytomegalovirus1960
TMV1960
vacuolating agent or virus1960
Coxsackie virus1961
rhinovirus1961
RSV1961
papovavirus1962
paramyxovirus1962
picornavirus1962
mycophage1963
parvovirus1965
rhabdovirus1966
Ross River virus1966
coronavirus1968
EBV1968
Epstein–Barr virus1968
leukovirus1968
CMV1969
arenovirus1970
oncornavirus1970
togavirus1970
alphavirus1971
calicivirus1971
Dane particle1971
flavivirus1971
flavovirus1971
maedi1971
orbivirus1971
mycovirus1972
visna-maedi virus1972
flu virus1973
maedi-visna virus1973
corona1974
orthopoxvirus1974
rotavirus1974
whitepox1974
retravirus1975
Ebola virus1976
morbillivirus1976
retrovirus1976
Ebola1977
lentivirus1979
reassortant1979
HTLV1980
morbilli1981
filovirus1982
LAV1983
CV1985
HIV1986
HIV virus1987
C-192020
Covid2020
Covid-192020
CV-192020
1906 Proc. Royal Soc. 1905–6 B. 77 319 A substance of this type would be considerably more affected by a change in the concentration of gelatine than a good filter-passer such as sodium chloride.
1913 J. McFadyean in XVIIth Internat. Congr. Med. IV. i. 50 The term ‘filter passers’ has been adopted..as the preferable name for the micro-organisms which..were..called the ultra-visible or invisible viruses.
2011 R. L. Atenstaedt Med. Response Trench Dis. v. 218 Substantial work was done on lice, ‘filter-passers’ and Rickettsia.
filter-passing adj. able to pass through a filter; = filterable adj. 1.
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the world > life > biology > organism > micro-organism > other micro-organisms > [adjective]
protococcoid1882
pathobiological1887
pathogermic1887
filter-passing1910
prokaryotic1957
mycoplasmal1959
protococcoidal1965
mycoplasma-like1967
methylotrophic1974
mycoplasmic1974
the world > life > biology > organism > micro-organism > virus > [adjective] > filterable
filterable1800
filter-passing1910
1910 Brit. Med. Jrnl. 9 Apr. 882/2 There is a tendency at present to ascribe many of the effects of the enteritis group to concomitant filter-passing agents.
1947 W. H. Auden Age of Anxiety (1948) v. 107 No filter-passing Virus invade.
1957 G. E. Hutchinson Treat. Limnol. I. vi. 385 They give the percentage effect of suspended or retained and dissolved or filter-passing material on the absorption.
2004 Limnol. & Oceanogr. 49 1525/2 Total and filter-passing MMHg [= monomethyl mercury] were also highest during low tide and lowest during high tide.
filter press n. [originally after French filtre-presse (1816 in the passage translated in quot. 1817)] a filter through which liquid is forced by the application of pressure.
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the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator > in which liquid is forced through by pressure
filtering press1817
filter press1817
1817 tr. in Repertory Arts, Manufs., & Agric. May 374 The filter-press [Fr. filtre-presse]..of which M. Hoyau has given an exact description, is the hydraulic lever of the English.
1889 Pall Mall Gaz. 2 May 7/1 The sludge is next forced into a filter press.
1954 Social & Econ. Stud. 2 77 There was also presumably a change in public taste toward the fine brown and white sugars produced by the centrifugal and the filter press.
2000 Paper Technol. Feb. 31/2 All dirty backwash/cleaning waters from the filter press..are recovered and returned to the head of the works.
filter pump n. a device in which liquid is forced through a filter by the action of a pump.
ΚΠ
1861 Farmer's Mag. Oct. 341/2 Improved combined filter pump, on plank, improved and manufactured by B. Fowler and Co., of Whitefriars, and T. Atkins and Son, of Fleet-street, price £5 10s.
1907 G. M. Norman Systematic Pract. Org. Chem. i. iv. 11 The crystals which separate are obtained by filtering with the filter-pump.
1979 Pop. Mech. Mar. 134 A typical hot tub is built of redwood, equipped with a heater to bring water temperature up to 105°F, a filter pump and a hydrojet pump to provide tub occupants with a massage effect.
2015 Nanaimo (Brit. Columbia) Daily News (Nexis) 9 July a5 Nanaimo's Beban Park leisure pool was out of commission Wednesday as city maintenance workers had to replace a filter pump that cleans the pool.
filter reactor n. Electronics (now rare) = filter inductor n.
ΘΚΠ
the world > matter > physics > electromagnetic radiation > electronics > electronic devices or components > [noun] > filter > part of
filter condenser1920
filter reactor1922
1922 A. F. Collins Bk. Wireless Telegr. & Telephone iii. iv. 194 The purpose of a filter reactor is to smooth out the pulsating direct current after it is produced by the rectifier tube.
1947 R. Lee Electronic Transformers & Circuits iv. 118 It is usually preferable to locate the filter reactors in the high-voltage lead.
2011 P. M. Curtis Maintaining Mission Crit. Syst. (ed. 2) x. 235 Constant losses associated with filter reactor/inductive elements significantly add to overall system losses.
filter shot n. a photograph or cinematographic sequence whose appearance is (esp. markedly) altered by the use of a filter.
ΘΚΠ
society > leisure > the arts > visual arts > photography > a photograph > [noun] > by method of photographing
melainotype1856
pistolgram1860
shot1867
snapshot1890
snap1894
telephotograph1894
Kodak1895
kite-photograph1897
close-up1913
vortograph1917
trick shot1924
Photomaton1927
rayograph1933
filter shot1937
flash1945
streak photograph1950
satellite picture1954
telephoto1960
digital photograph1962
xograph1974
digital photo1986
1937 Camera May 353/2 The color photographer must know panchromatism so perfectly that he can produce any possible filter shot with a minimum of study and without preliminary tests.
1969 Sight & Sound Spring 102/2 From a ‘typical’ filter shot of the evening sky, Jennings abruptly dissolves to a close-up of ‘Jacko’ Jackson lighting a cigarette in the bunkhouse.
2014 Sunday Tribune (Nexis) 27 July (Life section) 5 ‘Arty’, soft focus filter shots of what we had for lunch or dinner.
filter tip n. a cigarette filter; (also) a manufactured cigarette fitted with such a filter; = sense 4a.
ΘΚΠ
the world > physical sensation > use of drugs and poison > tobacco > smoking > articles or materials used in smoking > [noun] > thing which may be smoked > cigarette > filter
filter1870
filter tip1932
1932 Manch. Guardian 2 Mar. 9/7 A cigarette with a special filter tip.
1957 New Yorker 23 Nov. 100/2 When I ran out of American filter-tips, I chose the nearest equivalent I could find—a Bulgarian make.
2006 W. Self Bk. of Dave viii. 207 Dave lit another filter tip.
filter-tipped adj. (of a manufactured cigarette) fitted with a filter tip.
ΘΚΠ
the world > physical sensation > use of drugs and poison > tobacco > smoking > articles or materials used in smoking > [adjective] > type of cigarette
bird's eye1877
gold-tipped1890
mentholated1895
cork-tipped1907
king-size1909
roll-your-own1911
tailor-made1924
filter-tipped1927
king-sized1940
roll-up1948
filterless1956
tipped1964
untipped1968
unfiltered1976
1927 Brandon (Manitoba) Daily Sun 9 Sept. 7/4 A filter-tipped cigarette is another clever novelty.
1954 Newsweek 16 Aug. 72/3 The American Tobacco Co...brought out a filter-tipped version of Herbert Tareyton, its king-size and cork-tipped brand.
2013 A. Campion Death of Chef xxxii. 211 Lacroix tapped a filter-tipped Gitanes out of a soft pack.
filter tipping n. the action or process of fitting a cigarette with a filter tip; often attributive.
ΘΚΠ
the world > physical sensation > use of drugs and poison > tobacco > smoking > articles or materials used in smoking > [noun] > thing which may be smoked > cigarette > filter > filter-tipping
filter tipping1954
1954 Wall St. Jrnl. 18 Nov. 10/2 American Machine Foundry Co. has developed a new method of applying filter tips to cigarets which it claims ‘renders obsolete all other filter tipping devices currently used in the tobacco industry’.
1962 Financial Times 3 Oct. 5/4 The Mark 8 Cigarette Making Machine, together with Filter Tipping Attachment.
1999 S. J. Perkins Globalization (rev. ed.) vi. 154 The final rolling and filter tipping of the cigarettes.
This entry has been updated (OED Third Edition, September 2016; most recently modified version published online June 2022).
filterv.
/ˈfɪltə/, U.S. /ˈfɪltər/α. 1500s fyltre, 1500s–1600s fylter, 1500s–1800s filtre, 1500s– filter, 1600s feltre.
β. 1500s–1600s philter.
1.
a. transitive. To pass (a liquid) through a filter or porous medium in order to remove impurities. Later also more generally: to pass (air, light, etc.) through a filter in order to remove given components. Also occasionally intransitive.
ΘΚΠ
the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > filter [verb (transitive)]
drainc1000
felter1563
filter1576
transcolate1615
filtrate1639
1576 G. Baker tr. C. Gesner Newe Jewell of Health iv. f. 236v After Fyltre [L. effunde] the water, or let it runne through an Ippocrasse bagge.
1605 T. Tymme tr. J. Du Chesne Pract. Chymicall & Hermeticall Physicke i. ix. sig. F2v They dissolue many times, they fylter [L. filtrant], and coagulate.
1612 B. Jonson Alchemist ii. iii. sig. D4 Let the water in Glasse E. be feltred . View more context for this quotation
1672 N. Grew Anat. Veg. i. 21 The Sap..not being filtred through so fine a Cotton.
1716 Worlidge's Compl. Syst. Husbandry & Gardening iv. 97 Likewise do the same with Salt-peter, dissolve it in Water, filter the Water, and evaporate it.
1759 J. Wesley Primitive Physick (ed. 8) 88 Filtre the Tincture thro' Paper.
1838 T. Thomson Chem. Org. Bodies 200 We then filter, washing the blue-coloured sulphate of lime remaining on the filter till it becomes red.
1892 Pall Mall Gaz. 4 May 1/3 Each of these images is ‘filtered’ through a colour screen.
1958 J. C. Boursnell Safety Techniques for Radioactive Tracers iii. 13 In this case it is necessary to filter the outgoing air.
1991 Independent 30 Nov. 13/4 Filtering or boiling the water will not kill the algal toxins.
2004 C. P. Shaw Whisky (new ed.) 34 Burnt-sugar caramel may be added to bring a blend up to its desired colour before the whisky is filtered, bottled and labelled.
b. transitive. figurative and in figurative contexts. To put through a process likened to passing something through a filter, esp. so as to remove or alter certain aspects.
ΚΠ
1640 W. Davenant Salmacida Spolia sig. Cv A subtle quintessence..filtred through a melancholy brayne to make Eunuchs engender.
1678 C. V. tr. J. Barrin Monk Unvail'd 80 Having filtered as it were those two Orders [sc. the Franciscans and Augustinians].
1785 Asylum Fugitive Pieces 23 This measure appears to be filtered through the drip-stone of procrastination.
1798 Anti-Jacobin 9 July 283/2 Taught in her School t' imbibe thy mawkish strain, Condorcet, filter'd through the dregs of Paine.
1856 R. W. Emerson Eng. Traits i. 18 The passage would no doubt strike you more in the quotation than in the original, for I have filtered it.
1885 Manch. Examiner 10 Jan. 5/3 At present his instructions to counsel are filtered through a solicitor.
1912 I. S. Wile Sex Educ. i. 43 By filtering the information through the parents there is a constant adjustment of the facts to the child's understanding.
1987 C. Peters Thackeray's Universe vi. 122 He felt that reform was safest when it came from above, filtered through the educated, gentlemanly classes.
2014 S. Metzler B. Spranger 17/1 Quentin Metsys and his son Jan, Jan Gossart, and Bernard van Orley..had filtered the Italian Renaissance through their own Netherlandish traditions.
c. transitive. Of a filter, or something used as one: to remove impurities, unwanted material, etc., from (something). Also occasionally intransitive.
ΘΚΠ
the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > filter [verb (transitive)] > of filtering material
filter1790
1790 Monthly Rev. 2 549 The whole surface of the cone is to be covered with fine transparent gauze, which will serve to filter the air from any extraneous bodies floating in it.
1851 S. P. Woodward Man. Mollusca i. 37 The sea-weed filters the salt-water.
1882 H. Watts Dict. Chem. II. 648 Paper which filters slowly may be improved in quality by this treatment.
1935 Pop. Mech. Nov. 792/1 The unit filters the air and adds moisture to it.
1997 New Scientist 30 Aug. 13/3 £5000-worth of plantibodies will be able to filter 50 million litres of water a day.
2003 N.Y. Times (National ed.) 6 Feb. e5/2 Colors are created by a color wheel that filters the light.
d. transitive. Electronics. To pass (an electrical signal) through a filter which allows through only signal components with specific frequencies, and attenuates all others; to modify electrical signals from (a device) in this manner. Cf. filter n. 4d.Recorded earliest in to filter out 1 at Phrasal verbs.
ΘΚΠ
the world > matter > physics > electromagnetic radiation > electronics > electronic phenomena > processes > [verb (transitive)] > eliminate unwanted frequencies
filter1902
suppress1902
1902 Electr. Rev. 13 Sept. 340/1 A current curve, obtained by using a self-induction containing iron, in which the irregularities are filtered out.
1913 Telephony 23 Aug. 21/1 Alternating and direct currents may be mixed and then filtered.
1943 Bios 14 134 This current when suitably amplified and filtered, forms the signal current which controls the printer bar of a facsimile recorder.
1982 Giant Bk. Electronics Projects v. 182 To stop this LO feedthrough, the converter output is filtered.
1996 P. Trynka Rock Hardware 141/3 (Gloss.) Voltage-Controlled Filter... Controls the tonal character of a sound by filtering the frequencies produced by the VCO, using different cut-off parameters such as high-band, low-band, band-pass and notch.
2002 R. Schmitt Electromagnetics Explained xii. 273 Very sensitive circuits..require LC filters to filter the power supply.
e. transitive. To process or reformat (data, emails, etc.) using a filter (filter n. 4e), esp. so as to remove unwanted content.
ΚΠ
1968 Amer. Statistician 22 17/2 It combines the power to retrieve data (and do simple reckoning) with the ability to filter data.
1978 New Scientist 6 July 23/2 A Prime 300 minicomputer..will monitor the data, filter the measurements and compare them with known performance data.
1991 InfoWorld 30 Sept. 33/3 Cornerstone Agent monitors traffic on a network, filters data, and generates statistics.
2002 Network World 14 Jan. 30/4 The company..supplies a fee-based service that filters your e-mail for you.
2013 Manch. Evening News (Nexis) 10 Aug. 26 You can see the full predicted league table on our website and use the interactive graphic to filter the results.
2. transitive. To obtain, extract, or remove (something) by using a filter or a method likened to this. Also with off. See also to filter out 1 at Phrasal verbs.
ΘΚΠ
the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > filter [verb (transitive)] > remove or obtain by filtering
filter1576
leach1860
1576 G. Baker tr. C. Gesner Newe Jewell of Health iv. f. 236v The water Fyltred [L. aqua filtrata] from the grosser matter, poure into a bason.
1666 W. Austin Ἐπιλοίμια Ἔπη: Anat. Pestilence iii. 102 Such rust delimate, our gold bright will show. Filtre such dregs: from pest we run free too.
1785 W. Cowper Task ii. 71 Sages strove In vain, to filter off a chrystal draught Pure from the lees.
1845 C. Darwin Jrnl. (ed. 2) i. 5 Fine dust, which appeared to have been filtered from the wind by the gauze of the vane at the mast-head.
1874 F. Clowes Elem. Treat. Pract. Chem. 44 A precipitate which has been filtered from the liquid in which it is suspended.
1934 Webster's New Internat. Dict. Eng. Lang. Net plankton, plankton filtered from water by means of a specially constructed plankton net.
1966 B. Beatty Around Austral. 224 The residue left after the juices have been filtered from the crushings..makes a rich fertilizer.
2000 J. S. Kenny Views from Ridge 130/3 Blackfly larvae..filtering their food from the stream.
3.
a. intransitive. Esp. of a liquid: to pass through a filter; to percolate or seep through a porous medium. Usually with adverbial of direction, as through, down, etc. Occasionally also transitive (reflexive).
ΘΚΠ
the world > matter > liquid > liquid flow > percolation > pass through by percolation [verb (intransitive)]
oozea1398
soakc1440
filter1576
percolate1684
infiltrate1828
leach1883
the world > movement > motion in a certain direction > movement over, across, through, or past > [verb (intransitive)] > through > through a porous medium
sipec1000
oozea1398
soakc1440
filter1576
strain1590
transude1664
percolate1684
transudate1684
filtrate1686
seep1790
leach1883
1576 G. Baker tr. C. Gesner Newe Jewell of Health iii. f. 177v Now they take this Regulum, & soften it on a marble, on which they powre the distilled vineger, & when the same shall be very well softned: they put into an ypocrasse bagge to fylter [L. collocant in panno ex filtro].
1644 K. Digby Two Treat. i. xx. 183 That streame [of atoms]..clymbing and filtring it selfe along the stones streame.
1665 R. Hooke Micrographia 128 Some actuated unctuous parts..creep along and filter through some small string of the Week [= wick].
1721 R. Bradley Gen. Treat. Husbandry & Gardening II. 136 The raw Juices coming directly from the Earth, and mixing with those which have had a longer time to filter through the fine Vessels of the Tree, may cause a Fermentation.
1798 W. Blair Soldier's Friend App. 155 The water..will filter through the sand.
1817 W. Maclure Observ. Geol. U.S.A. iii. 68 Rocks..fall into granular pieces of an angular form, leaving spaces through which all minute particles..can filter along with the water.
1864 G. P. Marsh Man & Nature 437 A stratum of snow..causes almost all the water that composes it to filter down into the earth.
1917 Let. 7 Feb. in 3rd Ann. Rep. Dept. Health Mass. (1918) App. 294 The sewage of this school was disposed of for several years into a deep cesspool, from which it filtered away through the ground without objection.
1979 M. Matshoba Call me not Man 166 ‘While I am waiting for the water to filter through,’ she thought, ‘I will go and scrub my feet.’
2006 A. Steffen et al. Worldchanging (2008) 194/2 Permeable pavement..allows rainwater to filter through into the ground.
b. intransitive. figurative and in figurative contexts. To move or pass slowly or in small quantities through something; (of news or information) to propagate gradually. Usually with adverbial of direction, as through, in, etc.
ΚΠ
1821 J. Clare Village Minstrel I. 207 The sunbeams, filtering small, Freckling through the branches fall.
1868 E. Yates Rock Ahead I. i. iii. 158 A perpetual stream of..people..would filter from ten till one through her..drawing-rooms.
1909 J. R. Ware Passing Eng. Victorian Era 28 This phrase is probably one of the few that filter down in the world from Oxford.
1958 H. M. Hayward & M. Harari tr. B. Pasternak Dr. Zhivago ii. viii. 231 Although the station area was cordoned off..passengers for the local trains had managed, in some unaccountable way, to ‘filter through’ (as we would say now).
1969 Listener 27 Feb. 281/2 Meanwhile foreign literature (Ibsen and Chekhov notably) and painting (the Post-Impressionist Exhibition) were slowly filtering in.
1998 Independent 6 June (Mag.) 50/2 One variety [of avocado] I will be looking out for this summer is Edrinol, not as yet common over here, but starting to filter through.
2008 B. Friesen Bk. of Beasts (2011) 82 Then, as he walked, there were girls everywhere, and they didn't filter away, but processed in small groups in the same direction as the boys.
c. intransitive. Chiefly British. Of a road vehicle: to join traffic coming from another direction at a junction, esp. by turning left or right while traffic going straight ahead is halted by traffic lights. With preposition of direction (esp. into) or adverb.
ΘΚΠ
society > travel > transport > transport or conveyance in a vehicle > vehicular traffic > [verb (intransitive)] > join another line at junction
filter1928
1928 Traffic Signals to be used by Police & Drivers of Vehicles (H.M.S.O.) ii. 10 At road junctions, when one stream of traffic has been halted, constables should..permit drivers who wish to do so to turn to the left and so filter into the cross stream of moving traffic.
1937 V. Woolf Years 334 He filtered slowly round the corner.
1988 D. Lodge Nice Work i. i. 14 Vic leaves the residential area..and filters into the traffic moving sluggishly along the London Road.
2005 Cycling World Oct. 8 Consequently all the town traffic lights had been covered, making it a free for all with traffic merging from every direction to filter into a one way system.
ΘΚΠ
the world > matter > liquid > liquid which has been emitted > action or process of exuding > exude [verb (transitive)]
filter1582
exudate1671
exude17..
the world > matter > liquid > liquid flow > percolation > cause to percolate [verb (transitive)]
filter1582
percolate1626
leach1796
the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > filter [verb (transitive)] > cause to percolate
filter1582
percolate1626
filtrate1682
leach1796
the world > movement > motion in a certain direction > going or coming out > letting or sending out > let or send out [verb (transitive)] > emit > emit by exudation
sweat?c1225
oozea1398
distilc1400
constilc1430
degout?1504
stilla1530
spew1570
filter1582
deplore1601
evaporate1611
weep1634
collachrymate1657
elacrymate1657
exudate1671
exude17..
exstill1819
1582 R. Stanyhurst tr. Virgil First Foure Bookes Æneis iii. 45 The tre..of swart blud filtred abundance.
1658 T. Bromhall Hist. Apparitions 264 Stymphalus..maketh a great Lake or Gulph, and percollating, and being filtred through the Veins of the Earth, insinuates it self at length into the Argolick field.
1675 N. Grew Compar. Anat. Trunks ii. i. 47 The Vesiculæ..filtre or transfuse part of their Sap thereinto.
1791 European Mag. & London Rev. Oct. 279/2 Through the cracks and hollows of the surrounding wall of rock were filtered small and clear streams.
1852 M. F. Maury Explan. & Sailing Direct. (ed. 4) 53 Rivers..some of which are filtered through soils..which yield one kind of salts.
1900 A. Dorrington Castro's Last Sacrament & Other Stories 26 The rocks filtered great drops of mouth-cooling water into their outstretched hands.
Phrasal verbs
to filter out
1. transitive. To extract, remove, or separate using a filter (of various types) or a method likened to one.
ΘΚΠ
the world > space > place > removal or displacement > extraction > extract [verb (transitive)] > (as) by means of a sponge or filter
sponge1686
discuss1802
to filter out1823
1823 N.-Y. Med. & Phys. Jrnl. 2 521 After standing for a day the precipitate was filtered out.
1881 Eng. Mechanic 13 May 235/3 This was said to filter out the dark heat-rays.
1902Filtered out [see sense 1d]. 1951 R. E. Kirk & D. F. Othmer Encycl. Chem. Technol. VI. 516 The sand acts as the filter medium and filters out suspended solids.
1996 C. Jenkins in P. Trynka Rock Hardware 59/1 In conventional subtractive analog synthesis, the musician starts with a harmonically rich source, filtering out unwanted harmonics to define the sound.
2011 Herald-Times (Bloomington, Indiana) 30 July d3/2 Rainwater is absorbed into a vegetative roofing system, filtering out air pollutants and making cleaner water.
2. transitive. figurative. To remove or eliminate, esp. by a selective process; to block out.
ΘΚΠ
the mind > language > statement > refusal > [verb (transitive)] > dismiss from consideration
forheedc1275
sequesterc1380
forlaya1400
to lay awaya1400
to put, set or lay byc1425
to lay by1439
to lay asidec1440
to set, lay, put apart1477
bar1481
to lay apart1526
to throw out1576
disclude1586
to fling aside1587
to fling away1587
exclude1593
daff1598
to throw by1644
eliminate1850
to write off1861
to filter out1934
slam-dunk1975
1934 China Press (Shanghai) 7 Nov. 12 In order to filter out all government functionaries who secured their positions on personal recommendations by high officials.., an annual test should be held.
1965 N. Chomsky Aspects Theory Syntax 224 An extraneous factor..filters out certain latent interpretations provided by the deep structures.
1998 New Scientist 26 Sept. 23/2 The brain's capacity to filter out irrelevant background noise.
2013 Daily Tel. 15 Nov. 8/1 The Oxford University admissions system is designed to filter out ‘thick rich’ pupils and select on academic merit alone.
Derivatives
ˈfilterer n. something which filters, or which acts as a filter.
ΘΚΠ
the world > physical sensation > cleanness and dirtiness > freedom from impurities > removal of impurities > filtering or percolating > [noun] > filter or percolator
filterer1788
filter1791
percolator1842
1788 Med. Commentaries for 1787 Decade 2nd 2 47 Clothing may be considered as a filterer, separating the impurities of the air before it comes in contact with the body.
1809 J. F. Archbold Brit. Patent 3225 It [sc. sea water] is passed through a filterer.
1846 Catholic Herald (Philadelphia) 30 Aug. 272/4 Refrigerators, water coolers, and filterers.
1908 Practitioner Feb. 243 The spleen is, so to speak, a filterer of the blood.
1981 Daily Tel. 25 Apr. 8/8 These plants make better noise filterers than conifers do when used as hedging.
2006 A. G. van der Valk Biol. Freshwater Wetlands vi. 120 (caption) Invertebrate species are grouped by how they obtain their food (collector/gatherer, shredder, scraper, piercer-shredder, filterer, predator).
This entry has been updated (OED Third Edition, September 2016; most recently modified version published online June 2022).
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