from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A porous material through which a liquid or gas is passed in order to separate the fluid from suspended particulate matter.
  • noun A device containing such a material, especially one used to extract impurities from air or water.
  • noun Any of various electric, electronic, acoustic, or optical devices used to reject signals, vibrations, or radiations of certain frequencies while allowing others to pass.
  • noun A colored glass or other transparent material used to select the wavelengths of light allowed to reach a photosensitive material.
  • noun Computers A program or device that blocks e-mail or restricts website access when specific criteria are met.
  • intransitive verb To pass (a liquid or gas) through a filter.
  • intransitive verb To remove by passing through a filter.
  • intransitive verb Computers To use a filter to block or restrict access to.
  • intransitive verb To pass through or as if through a filter.
  • intransitive verb To come or go gradually and in small groups.

from The Century Dictionary.

  • noun A device for arresting and separating any matter mechanically suspended in a liquid.
  • noun Specifically In fish-culture, a long box in which screens, usually of flannel, are placed, through which the water is filtered before it passes into the hatching-troughs. Also called filtering-box, filtering-tank.
  • Same as felter.
  • noun See philter.
  • To purify or defecate, as water or other liquid, by passing it through a filter or any cleansing medium; strain.
  • Specifically In analytic chemistry, to separate (a solution) from the solid matter contained in it, either for the purpose of collecting and saving the solid matter, usually a precipitate, or of preparing the solution for further operations.
  • To percolate; pass through or as through a filter.

from the GNU version of the Collaborative International Dictionary of English.

  • noun Same as philter.
  • transitive verb To purify or defecate, as water or other liquid, by causing it to pass through a filter.
  • transitive verb a porous unsized paper, for filtering.
  • intransitive verb To pass through a filter; to percolate.
  • noun Any porous substance, as cloth, paper, sand, or charcoal, through which water or other liquid may passed to cleanse it from the solid or impure matter held in suspension; a chamber or device containing such substance; a strainer; also, a similar device for purifying air.
  • noun a pond, the bottom of which is a filter composed of sand gravel.
  • noun an underground gallery or tunnel, alongside of a stream, to collect the water that filters through the intervening sand and gravel; -- called also infiltration gallery.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A device which separates a suspended, dissolved, or particulate matter from a fluid, solution, or other substance; any device that separates one substance from another.
  • noun Electronics or software that separates unwanted signals (for example noise) from wanted signals or that attenuates selected frequencies.
  • noun Any item, mechanism, device or procedure that acts to separate or isolate.
  • noun mathematics, order theory A non-empty upper set (of a partially ordered set) which is closed under binary infima (a.k.a. meets).
  • verb transitive To sort, sift, or isolate.
  • verb transitive To diffuse; to cause to be less concentrated or focused.
  • verb intransitive To pass through a filter or to act as though passing through a filter.
  • verb intransitive To move slowly or gradually; to come or go a few at a time.
  • verb intransitive To ride a motorcycle between lanes on a road

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • verb run or flow slowly, as in drops or in an unsteady stream
  • verb pass through
  • verb remove by passing through a filter
  • noun an electrical device that alters the frequency spectrum of signals passing through it
  • noun device that removes something from whatever passes through it


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English filtre, from Old French, from Medieval Latin filtrum, of Germanic origin; see pel- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

(noun) From Medieval Latin filtrum, from West Germanic *filtiz.


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  • Filth!

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  • Scandal!

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  • Cursitis!

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