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filter

n. · v.
US //ˈfɪɫtɝ// UK //fˈɪltɐ// fil·ter
  1. 1 cleaning device (n.)
    B1 Intermediate

    a device that removes dirt or unwanted pieces from a liquid or gas.

    a porous device or substance used to separate suspended particulate matter from a fluid.

    Example

    You need to change the water filter every six months to keep the water clean.

    Example

    The industrial ventilation system utilizes a high-efficiency particulate air filter to ensure the laboratory remains free of contaminants.

    Usage

    often used with 'water', 'air', or 'coffee' as a modifier.
  2. 2 digital image effect (n.)
    A2 Elementary Computing

    a software tool that changes how a photo or video looks, often used on social media.

    a digital image processing effect that alters the appearance of a photograph or video stream.

    Example

    She used a vintage filter to make her new photos look like they were from the 1970s.

    Example

    Social media platforms offer a variety of augmented reality filters that can modify facial features in real-time during video calls.
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  1. 3 self-restraint in speech (n.)
    B2 Upper Intermediate Informal

    the ability to think before you speak so you do not say something rude or inappropriate.

    the psychological or social capacity for self-censorship and restraint in verbal communication.

    Example

    Sometimes he says exactly what he thinks because he has no filter.

    Example

    In casual settings, her lack of a social filter is charming, but it can be problematic during formal business negotiations.

    Usage

    usually used with 'no' or 'a' in phrases like 'he has no filter'.
  2. 4 to remove unwanted parts (v.)
    B1 Intermediate

    to pass a liquid or gas through a device to clean it.

    to pass a substance through a medium to remove impurities or specific components.

    Example

    The sunlight was filtered by the thick leaves of the trees.

    Example

    The kidneys work constantly to filter waste products from the blood and maintain chemical balance.
  3. 5 to move slowly (v.)
    B2 Upper Intermediate

    to move or spread slowly, often a few people or things at a time.

    to move, seep, or communicate gradually or in small quantities.

    Example

    News about the company's closing began to filter out to the employees.

    Example

    After the concert ended, the audience began to filter out of the stadium and into the nearby subway stations.

    Usage

    often used with prepositions like 'through', 'in', or 'out'.
  4. 6 to ride between lanes (v.)
    C1 Advanced British English

    to ride a motorcycle or bicycle between lanes of slow-moving cars.

    to navigate a two-wheeled vehicle between lanes of stationary or slow-moving traffic.

    Example

    The motorcyclist filtered through the heavy traffic to reach the front of the queue.

    Example

    While filtering is legal in many jurisdictions, riders must exercise extreme caution when passing between large commercial vehicles.
    • lane splitting
Origin

From Middle English filtre, from Medieval Latin filtrum (compare also Old French feutre (“felt; filter”)), from Frankish filtir, from Proto-West Germanic felt. See felt. Doublet of phin.

Idioms2 entries

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