clean is on the Basic English 850 List.
circle - clean - clear
clean is one of the 1000 most common headwords.
class - clean - clear

Pronunciation

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Adjective

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Positive
clean

Comparative
cleaner

Superlative
cleanest

 
A clean car
  1. If something is clean, it is free from dirt
    The kids came back from the washroom with clean hands and faces.
    Did you wash these dishes? They don't look very clean.
    To keep the air clean, smoking is not allowed.
    I clear our breakfast and wipe the table clean with a wet rag.
  2. If a technology is clean, it doesn't produce much pollution.
    We want to use wind as safe, clean, non-polluting energy.
  3. If something is clean, it is not bad.
    There was a lot of pushing in their last game, but today's match was mostly clean.
    No dirty jokes, please. Keep your language clean.
    The police searched the car for drugs, but it was clean.
    Her driving record was clean.
  4. (usually before a noun) A clean piece of paper, start, etc. has nothing from before: no writing, no history, etc.
    Why don't you get a clean piece of paper and start over.
    I wanted a clean start, so I moved to LA.
  5. If a something is clean, it is smooth, simple, and regular, without anything unwanted.
    Your company website needs a clean design that makes it easy for consumers to understand what you're selling.
    It's a clean cut, made with something sharp like a razor or a knife.
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Plain form
clean

Third-person singular
cleans

Past tense
cleaned

Past participle
cleaned

Present participle
cleaning

 
A man cleaning a boat
  1. (transitive & intransitive) If you clean something, you take away the dirt and put everything in its place.
    Tomo, will you clean up your room please. There are clothes all over the floor.
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