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noun fil·ter \ˈfil-tər\

Simple Definition of filter

  • : a device that is used to remove something unwanted from a liquid or gas that passes through it

  • : a device that prevents some kinds of light, sound, electronic noises, etc., from passing through

  • computers : software that prevents someone from looking at or receiving particular kinds of material through the Internet

Full Definition of filter

  1. 1 a :  a porous article or mass (as of paper or sand) through which a gas or liquid is passed to separate out matter in suspension b :  an apparatus containing a filter medium

  2. 2 a :  a device or material for suppressing or minimizing waves or oscillations of certain frequencies (as of electricity, light, or sound) b :  a transparent material (as colored glass) that absorbs light of certain wavelengths or colors selectively and is used for modifying light that reaches a sensitized photographic material —called also color filter

  3. 3 :  something that has the effect of a filter (as by holding back elements or modifying the appearance of something) <his work is too often viewed through the filter of race — Brent Staples>

  4. 4 :  software for sorting or blocking access to certain online material

Examples of filter

  1. She smokes cigarettes with filters.

  2. He placed a red filter on the camera lens.

  3. digital filters that stop high-frequency sounds

Origin of filter

Middle English filtre, from Medieval Latin filtrum piece of felt used as a filter, of Germanic origin; akin to Old High German filz felt — more at felt

First Known Use: 1563

Other Chemical Engineering Terms

Rhymes with filter



verb fil·ter

Simple Definition of filter

  • : to pass (something, such as a gas or liquid) through a filter to remove something unwanted

  • : to remove (something unwanted) by using a filter

  • : to move through or into something in small amounts or in a gradual way

Full Definition of filter

fil·teredfil·ter·ing play \-t(ə-)riŋ\

  1. transitive verb
  2. 1 :  to subject to the action of a filter

  3. 2 :  to remove by means of a filter

  4. intransitive verb
  5. 1 :  to pass or move through or as if through a filter

  6. 2 :  to come or go in small units over a period of time <people began filtering in>

Examples of filter

  1. They've begun filtering their water to remove impurities.

  2. a device that filters impurities from water

  3. sunglasses that filter ultraviolet light

  4. Sunlight filtered through the leaves.

  5. His ideas have filtered down to his children.

  6. The crowd filtered into the arena.

  7. Early election returns have begun to filter in.


First Known Use of filter


Seen and Heard

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February 14, 2016

to hug and kiss another person

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