filter

1 of 2

noun

fil·​ter ˈfil-tər How to pronounce filter (audio)
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
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 (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 raceBrent Staples
4
: software for sorting or blocking access to certain online material

filter

2 of 2

verb

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

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

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.
Recent Examples on the Web
Noun
Step 4: Place filter (or filters) into the mixing bowl with cleaning solution. Kaitlyn Yarborough, Southern Living, 17 Mar. 2024 Options include two specific filters: subtle and smoothing. Emily Price, PCMAG, 16 Mar. 2024 There’s no little aluminum tab to pull off at the top, no plastic cup or internal filter to dispose of afterward. Jaina Grey, WIRED, 13 Mar. 2024 Social media filters added in the video alter both of their appearances, including making their eyes bulge and putting long noses on their faces. USA TODAY, 9 Mar. 2024 Remember to use proper eye protection, such as eclipse glasses or solar filters, to safely view the eclipse. The Arizona Republic, 8 Mar. 2024 Palm leaf blunts and corn husk filters are also found to frequently fail for heavy metals, pesticides and microbial contamination. Harrison Bard, Rolling Stone, 1 Mar. 2024 The filter must be made specifically for solar viewing, Stocks said. Anthony Robledo, USA TODAY, 3 Mar. 2024 The next filter of the AAII Lakonishok screen requires that the 13-week relative strength of a company is equal to or greater than the 26-week relative strength. Charles Rotblut, Forbes, 29 Feb. 2024
Verb
The three-stage filtration system can filter airborne particles like dust, pollen, pet dander, bacteria, viruses, and mold spores. Nora Colomer, Fox News, 18 Mar. 2024 Commercial producers rely on reverse osmosis machines — which filter a decent bit of water from the sap before boiling — and powerful evaporators. Ashley Stimpson, Washington Post, 12 Mar. 2024 Seven decades later, researchers found actual erythropoietin after filtering 670 gallons of urine. Carl Zimmer, New York Times, 10 Mar. 2024 Once that sunscreen has hit its expiration date, the formula will begin to separate and those active ingredients that filter out the UV rays may end up clustering in one area upon application. Audrey Noble, Vogue, 9 Mar. 2024 The 2013 study, also by Tourism Economics, found that Summerfest's economic impact in Milwaukee was $187 million, with an additional $39 million filtering through the state. Journal Sentinel, 7 Mar. 2024 It can be collected, filtered and made drinkable or used for other purposes. Letters To The Editor, The Mercury News, 5 Mar. 2024 Now, new research suggests that a simple, cheap measure may significantly reduce the level of microplastics in water from your tap: boiling and filtering it. Christian Thorsberg, Smithsonian Magazine, 1 Mar. 2024 Even allowing for the nostalgic gauze filtering the lens of memory, studio veterans speak of Paramount as kind of backlot Camelot. Thomas Doherty, The Hollywood Reporter, 29 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'filter.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

Middle English filtre "felt, felt carpet, piece of felt used as a filter," borrowed from Medieval Latin filtrum "felt cloth, cover or blanket of felt, piece of felt used as a filter," borrowed from *filtir (going back to *filtizō) in a West Germanic language, plural of *filt-, *felt- "felted cloth" — more at felt entry 1

Verb

derivative of filter entry 1

First Known Use

Noun

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

Verb

1576, in the meaning defined at transitive sense 1

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

Dictionary Entries Near filter

Cite this Entry

“Filter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/filter. Accessed 29 Mar. 2024.

Kids Definition

filter

1 of 2 noun
fil·​ter ˈfil-tər How to pronounce filter (audio)
1
: a substance with pores through which a gas or liquid is passed to separate out floating matter
2
: a device containing a filter
3
: a transparent material (as colored glass) that absorbs light of some wavelengths and is used to change light (as in photography)

filter

2 of 2 verb
filtered; filtering -t(ə-)riŋ How to pronounce filter (audio)
1
: to expose to the action of a filter
2
: to remove by means of a filter
3
: to pass through or as if through a filter

Medical Definition

filter

1 of 2 noun
fil·​ter ˈfil-tər How to pronounce filter (audio)
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
3
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

filter

2 of 2 verb
filtered; filtering -t(ə-)riŋ How to pronounce filter (audio)

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

More from Merriam-Webster on filter

Last Updated: - Updated example sentences
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