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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.

    1. a.
      [intransitive] to become smaller in number, amount, or size
  2. 2



    thin out

    [transitive] to remove plants, leaves, trees etc so that they do not fill an area or space completely
    Synonyms and related words
  3. 3
    [intransitive] if someone’s hair thins, they gradually lose the hair from their head

    a man with grey thinning hair

  4. 4
    [transitive] to make a thick liquid become less thick by adding water or another liquid to it


used to describe something which is done more carefully and over a longer period of time …

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the practice of giving birth in the presence of several friends and relatives

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