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English definition of “idea”

idea

noun  /ɑɪˈdi·ə/ us  

idea noun (SUGGESTION)

[C] a suggestion, thought, or plan: "Let’s go swimming." "Good idea!" She’s full of bright ideas.

idea noun (KNOWLEDGE)

[C/U] knowledge or understanding about something: [C] Can you give me a rough idea of the cost (= tell me approximately how much it will cost)? [U] You have no idea what I just said, do you?

idea noun (BELIEF)

[C] a belief about something: They have some unusual ideas about parenting.

idea noun (PURPOSE)

[C usually sing] a purpose or reason for doing something: The idea behind the law is to raise money for education.
(Definition of idea from the Cambridge Academic Content Dictionary © Cambridge University Press)
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