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English definition of “brain”

brain

noun     /breɪn/
A2 [C] the organ inside the head that controls thought, memory, feelings, and activity: Doctors tried desperately to reduce the swelling in her brain. The accident left him with permanent brain damage. His wife died from a brain tumour.The brain and nervous system C1 [C] used to refer to intelligence: Marie has an amazing brain (= is very intelligent). That can't possibly be the right way to do it - use your brain! The poor child inherited his mother's brains and his father's looks. He's got brains but he's too lazy to use them (= he is clever but lazy).The brain and nervous systemIntelligencePerceptive [C usually plural] informal a very intelligent person, especially one who has spent a lot of time studying: We've got the best brains in the land working on this problem.Intelligent people the brains [S] the cleverest person of a group, especially the person who plans what the group will do: My little brother's the brains of the family.Intelligent people
(Definition of brain noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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