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thin - definition and synonyms


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verb thin pronunciation in British English /θɪn/
Word Forms
present tense
present participlethinning
past tensethinned
past participlethinned
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  1. 1



    thin down

    [transitive] to make something smaller in number, amount, or size
    Sales have decreased and we’ve decided to thin our workforce.
    Police thinned down the crowd.
  2. 2



    thin out

    [transitive] to remove plants, leaves, trees etc so that they do not fill an area or space completely
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  3. 3
    [intransitive] if someones hair thins, they gradually lose the hair from their head
    a man with grey thinning hair


a meal served in the evening which consists of foods traditionally eaten at breakfast

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troll factory

a company that pays its employees to write online comments in favour or against somebody or something posing as ordinary Internet users

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