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thin - definition and synonyms

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verb     thin pronunciation in British English
Word Forms
present tense
present participlethinning
past tensethinned
past participlethinned
  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
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  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


a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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