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scum - definition and synonyms

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noun [uncountable]     scum pronunciation in British English
  1. 1
    a layer of a dirty or unpleasant substance that forms on the surface of a liquid

    A thick layer of black scum lay on the canal water.

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  2. 2
    offensive an insulting word for someone who you think is very unpleasant

    The people who do these dreadful things are scum.

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