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brain - definition and synonyms

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noun     brain pronunciation in American English
Word Forms
  1. 1
    [countable] the organ inside your head that allows you to think and feel, and controls your body

    The human brain is divided into two halves.

    1. a.
      [only before noun] belonging to or connected with the brain
    2. b.


      [plural] the brain of an animal cooked and eaten as food
      Synonyms and related words
  2. 2
    [countable] [often plural] mental ability or intelligence

    You have to use your brains in this job.

    have brains/a brain (=be intelligent):

    He’s good-looking, and he has brains.

  3. From our crowdsourced Open Dictionary
    have a brain the size of a planet to be extremely clever (originally said of Marvin the paranoid android in The Hitchhiker's Guide to the Galaxy)

    It's James, he has a brain the size of a planet!

    Submitted by James Strangward from United Kingdom on 19/05/2014


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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