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REFERENCE

clean

v. · adj. · n. · adv.
US //ˈkɫin// UK //klˈiːn// clean
  1. 1 to remove dirt (v.)
    A1 Beginner

    to remove dirt, marks, or stains from something.

    to remove impurities, dirt, or foreign matter from a surface or object. Transitive and intransitive uses are common.

    Example

    I need to clean my glasses because I can't see through the smudges.

    Example

    The restoration team had to clean the fresco with extreme caution to avoid damaging the original sixteenth-century pigments.
  2. 2 to tidy a room (v.)
    A1 Beginner

    to make a place neat and organized.

    to organize or tidy a space by removing clutter and arranging items properly.

    Example

    Please clean your room before your friends arrive for the party.

    Example

    The staff worked quickly to clean the conference hall between sessions, ensuring every chair was aligned and all litter removed.
    • mess up
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  1. 3 not dirty (adj.)
    A1 Beginner

    free from dirt, marks, or bad smells.

    free from dirt, pollutants, or contamination; in a state of hygiene.

    Example

    Put on a clean shirt for the interview so you look professional.

    Example

    The laboratory requires a clean environment to ensure that no outside bacteria interfere with the sensitive chemical cultures.
  2. 4 honest or legal (adj.)
    B2 Upper Intermediate

    not involved in anything illegal or dishonest.

    free from criminality, immorality, or prohibited substances; often used regarding a person's record or a sports drug test.

    Example

    The driver had a clean record with no accidents for ten years.

    Example

    The athlete insisted he was clean, pointing to the results of three independent drug tests conducted during the off-season.
  3. 5 environmentally friendly (adj.)
    B1 Intermediate Science

    not causing much pollution or damage to nature.

    producing little or no pollution or hazardous waste; sustainable.

    Example

    Solar power is a clean energy source that helps protect the planet.

    Example

    The government is subsidising the transition to clean technologies to meet its carbon reduction targets by the end of the decade.
  4. 6 smooth and precise (adj.)
    B2 Upper Intermediate

    done in a smooth, simple, and perfect way.

    characterised by smooth lines, precise execution, or a lack of unnecessary complexity.

    Example

    The knife made a clean cut through the thick rope.

    Example

    The architect is known for the clean lines of her buildings, avoiding the decorative clutter common in traditional designs.
  5. 7 an act of cleaning (n.)
    A2 Elementary

    the act of making something clean.

    an instance or process of cleaning something. Usually follows 'give something a...'.

    Example

    The kitchen needs a good clean after all that cooking.

    Example

    The apartment was given a thorough clean before the new tenants moved in, leaving the floors polished and the windows sparkling.
  6. 8 completely (adv.)
    B2 Upper Intermediate Informal

    completely or totally.

    entirely or completely; often used to emphasize that something was missed or forgotten.

    Example

    I clean forgot to call my mother on her birthday.

    Example

    The thief managed to get clean away before the police could set up a perimeter around the building.
Origin

From Middle English clene, clane, from Old English clǣne (“clean, pure”), from Proto-West Germanic klainī (“shining, fine, splendid, tender”), perhaps from Proto-Indo-European glēy- (“gleaming”), from Proto-Indo-European *gel- (“to gleam”). Cognate with Scots clean (“absolute, pure, clear, empty”) and clene, clane (“clean”), North Frisian klien (“small”), West Frisian klien (“small”), klean (“clean”), Dutch klein (“small”), Low German kleen (“small”), German klein (“small”), Swedish klen (“weak, feeble, delicate”), Icelandic klénn (“poor, feeble, petty, snug, puny, cheesy, lame”).

Word family
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