English Reference
noun · verb

fuzz

n. · v.
US /ˈfəz/ UK /fˈʌz/ fuzz UK spelling fuzzed, fuzzes

  1. 01 B2 Upper Intermediate

    n.a mass of very fine, soft hair or fibers, like the surface of a peach.

    n.a frizzy or fine mass of hair, down, or fiber. Uncountable in its general sense.

    Simple

    The new sweater left little bits of white fuzz all over my black trousers.

    In context

    A fine layer of golden fuzz covered the surface of the ripening fruit, catching the afternoon light.

  2. 02 C1 Advanced SlangInformal

    n.a slang word for the police.

    n.a collective slang term for law enforcement officers or agencies. Usually used with the definite article.

    Simple

    We had to leave the party quickly before the fuzz showed up.

    In context

    The protagonist spent the first half of the novel trying to stay one step ahead of the fuzz.

  3. 03 B2 Upper Intermediate Music

    n.a blurry quality in a picture or a distorted sound from a guitar.

    n.visual blurring or acoustic distortion, particularly the saturated sound produced by an electric guitar.

    Simple

    The old television had so much fuzz on the screen that I couldn't see the players.

    In context

    The guitarist used a vintage pedal to add a heavy layer of fuzz to the opening riff of the song.

  4. 04 C1 Advanced Technical Computing

    n.random or messy data used to test if a computer program crashes.

    n.randomly generated data used as input for fuzz testing to identify software vulnerabilities.

    Simple

    The developer used fuzz to see if the new app could handle unexpected inputs.

    In context

    After injecting several gigabytes of fuzz into the interface, the security team identified a critical memory leak.

    random data
  5. 05 B2 Upper Intermediate

    v.to make something look less clear or sharp.

    v.to make a visual image or a conceptual boundary blurred or indistinct.

    Simple

    The steam from the shower started to fuzz the reflection in the mirror.

    In context

    The author deliberately chose to fuzz the line between reality and dreams throughout the final chapter.

  6. 06 C1 Advanced Technical Computing

    v.to test a computer program by giving it lots of random information.

    v.to perform fuzz testing on a software component by providing it with semi-random data.

    Simple

    We need to fuzz the new login system to make sure it is secure.

    In context

    The QA engineers decided to fuzz the API endpoints for forty-eight hours to ensure maximum coverage of potential edge cases.

    stress test

Quince is a hard, gold-coloured fruit that looks a bit like a mini apple or a pear and is covered in peach-like fuzz.

The Local· 28 Aug 2026

Etymology 1

Uncertain. Some dictionaries suggest a Germanic source; compare Low German fussig (“loose; spongy”), Dutch voos (“unsound; rotten”). Others, such as Webster's New College Dictionary, suggest a back-formation from fuzzy. The Oxford English Dictionary suggests, “Perhaps imitative of the action of blowing away light particles.”

Etymology 2

Unknown. Godfrey Irwin (1930) suggests a possible connection to fuss, "over-particular", excessive bother.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C1 · Advanced
Frequency Occasional
Updated