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English definition of “idea”

idea

noun (KNOWLEDGE)    /aɪˈdɪə/
B2 [S or U] an understanding, thought, or picture in your mind: Do you have any idea of what he looks like? Can you give me an idea of the cost (= can you tell me approximately how much the cost is)? I don't like the idea of living so far away from my family. [+ question word] I haven't the slightest/faintest idea where they've gone. I've got a pretty good idea why they left early.Ideas, concepts and theoriesKnowledge and awareness have no idea B1 informal to not know something: "Where's Serge?" "I've no idea".
(Definition of idea noun (KNOWLEDGE) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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