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cap - definition and synonyms

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noun [countable]     cap pronunciation in British English
Word Forms
  1. 1
    a soft hat with a stiff part called a peak that comes out over your eyes

    a baseball cap

    an elderly man in a peaked cap

    1. a.
      a soft hat that people wear as part of a uniform

      a nurse’s/chauffeur’s/sailor’s cap

      a school cap

    2. b.
      a soft hat that you wear to protect or cover your hair

      a swimming/bathing/shower cap

  2. 2
    a lid or part that fits over the top of something

    Meg screwed the cap back on the bottle.

  3. 4
    literary the top part of a mountain

    the hills with their snowy caps

    1. a.
      the top part of a wave
  4. 5
    a hard cover fixed to a tooth to protect it or replace part of it
    Synonyms and related words
  5. 6
    British if a football, rugby, or cricket player wins a cap, they play for their country in an international match
    win/receive/get a cap:

    He won seventeen caps for England in the 1990s.

    1. a.
      a player who has played for their country’s team

      Barber is joined in the midfield by the England cap Nick Pickering.

  6. 7



    Dutch cap

    British a rubber object that a woman puts inside her vagina so that she can have sex without getting pregnant
  7. 8
    a small amount of explosive that is used to make a loud noise in a toy gun called a cap gun
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