filter

noun
fil·​ter | \ ˈfil-tər How to pronounce filter (audio) \

Definition of filter

 (Entry 1 of 2)

1a : 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
2a : a device or material for suppressing or minimizing waves or oscillations of certain frequencies (as of electricity, light, or sound)
b : a transparent material (such 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 : 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 : software for sorting or blocking access to certain online material

filter

verb
filtered; filtering\ ˈfil-​t(ə-​)riŋ How to pronounce filter (audio) \

Definition of filter (Entry 2 of 2)

transitive verb

1 : to subject to the action of a filter
2 : to remove by means of a filter

intransitive verb

1 : to pass or move through or as if through a filter
2 : to come or go in small units over a period of time people began filtering in

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Synonyms for filter

Synonyms: Verb

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Examples of filter in a Sentence

Noun She smokes cigarettes with filters. He placed a red filter on the camera lens. digital filters that stop high-frequency sounds Verb They've begun filtering their water to remove impurities. a device that filters impurities from water sunglasses that filter ultraviolet light Sunlight filtered through the leaves. His ideas have filtered down to his children. The crowd filtered into the arena. Early election returns have begun to filter in.
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Recent Examples on the Web: Noun The Braintree Water and Sewer Department installed one filter to try to remove the chemicals, and, after seeing improvement, installed four more filters. BostonGlobe.com, "‘Forever chemicals’ removed from Braintree’s water," 13 Apr. 2021 One accessory that isn’t supplied with the AT2035 is a foam windshield or pop filter. Mark Sparrow, Forbes, "This Affordable Condenser Microphone From Audio-Technica Won’t Let You Down," 9 Apr. 2021 When used correctly, each filter can reportedly provide up to 4,000 liters of clean and safe drinking water. Christine Persaud, USA TODAY, "The Lifestraw portable water filter is a huge hit with Amazon shoppers—and less than $15," 9 Apr. 2021 Give your lawnmower a tuneup: change the oil, air filter and spark plug. Allen Foster, chicagotribune.com, "Lawn care: Best practices for spring and summer," 24 Mar. 2021 Add the photo filter and music to your video to make your own MV in the app. Maren Estrada, BGR, "Amazon double coupon deal cuts this awesome foldable 4K camera drone to just $60," 23 Mar. 2021 Rain that falls on solid surfaces such as sidewalks, roads and roofs, collects the pollutants on these surfaces, bypassing the natural filter process, and carries them directly into waterways such as the Columbia River. oregonlive, "Learn to build a Pacific Northwest rain garden," 23 Mar. 2021 The eagle shark might have had tiny, pointed teeth like the basking shark and the megamouth—two modern filter-feeding sharks—or taken a different strategy. Theresa Machemer, Smithsonian Magazine, "Discovery of a 95-Million-Year-Old ‘Eagle Shark’ Fossil Makes Waves," 22 Mar. 2021 AIRism mask is built with three layers of fabric, including a non-woven filter and an inner mesh layer that’s soft against skin and helps block UV rays. Zoe Malin, NBC News, "Notable launches from Nintendo, Uniqlo, Madewell, Blueair, Schick and more," 22 Mar. 2021 Recent Examples on the Web: Verb The Coredy vacuum comes with several tools and accessories, like a water tank, mop cloths, an extra high efficiency particulate air (HEPA) filter, and boundary strips. Christina Butan, PEOPLE.com, "PSA: This Top-Rated Robot Vacuum-Mop Is Secretly $100 Off on Amazon Right Now," 7 Apr. 2021 These findings will gradually filter out into the world’s markets, doubtless pushing more investors to divest. Bill Mckibben, The New Yorker, "The Powerful New Financial Argument for Fossil-Fuel Divestment," 3 Apr. 2021 With 64 teams needing to filter through the Convention Center for daily testing, NCAA officials choreographed every step, including when each program is granted access to its hotel’s elevator. Greg Luca, San Antonio Express-News, "Success of NCAA women's tournament in San Antonio hinges on meticulous COVID-19 protocols," 20 Mar. 2021 If Democrats lower the exemption to $3 or $3.5 million, as has been floated, that urgency would filter down to a less affluent group of clients. Jason Bisnoff, Forbes, "Tax Hikes Are Coming. Here’s What Top Advisors Are Telling The Ultra Rich," 18 Mar. 2021 Soon after that, a police vehicle pulled up as residents, including a child on a scooter, continued to filter in and out of the building. New York Times, "Man Arrested in Anti-Asian Attack Was on Parole for Killing His Mother," 31 Mar. 2021 But if you're still enticed by the idea of adding plants to filter out a few extra toxins in your air, and boost your mental health at the same time, there's literally no downside to stocking up. Arricca Elin Sansone, House Beautiful, "The 10 Best Houseplants for Cleaner Air," 31 Mar. 2021 Metz describes how a neural net at Google began identifying Black people as gorillas, and how one meant to filter out pornographic images had far more false positives with Black people than white people. Los Angeles Times, "Review: AI’s humble beginnings and potentially sinister future," 29 Mar. 2021 This is not a microphone for use in a noisy office environment where there are far too many sounds to filter out. Mark Sparrow, Forbes, "JLab’s Talk Pro Podcast Microphone Comes Packed With Useful Features," 20 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'filter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of filter

Noun

15th century, in the meaning defined at sense 1a

Verb

1576, in the meaning defined at transitive sense 1

History and Etymology for filter

Noun

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

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Time Traveler for filter

Time Traveler

The first known use of filter was in the 15th century

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Statistics for filter

Last Updated

17 Apr 2021

Cite this Entry

“Filter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/filter. Accessed 18 Apr. 2021.

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More Definitions for filter

filter

noun

English Language Learners Definition of filter

 (Entry 1 of 2)

: 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

filter

verb

English Language Learners Definition of filter (Entry 2 of 2)

: 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

filter

noun
fil·​ter | \ ˈfil-tər How to pronounce filter (audio) \

Kids Definition of filter

 (Entry 1 of 2)

1 : a device or a mass of material (as sand or paper) with tiny openings through which a gas or liquid is passed to remove something The filter removes dust from the air.
2 : a transparent material that absorbs light of some colors and is used for changing light (as in photography)

filter

verb
filtered; filtering

Kids Definition of filter (Entry 2 of 2)

1 : to pass through a filter filter water
2 : to remove by means of a filter Sand helps filter impurities from water.

filter

noun
fil·​ter | \ ˈfil-tər How to pronounce filter (audio) \

Medical Definition of filter

 (Entry 1 of 2)

1 : a porous article or mass (as of paper or sand) through which a gas or liquid is passed to separate out matter in suspension
2 : an apparatus containing a filter medium
3a : 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

filter

verb
filtered; filtering\ -​t(ə-​)riŋ How to pronounce filter (audio) \

Medical Definition of filter (Entry 2 of 2)

transitive verb

1 : to subject to the action of a filter
2 : to remove by means of a filter

intransitive verb

: to pass or move through or as if through a filter

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Comments on filter

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