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English definition of “mad”

mad

adjective (MENTALLY ILL)    /mæd/ (madder or maddest)
B1 mentally ill, or unable to behave in a reasonable way: I think I must be going mad. Do I look like some mad old woman in this hat? → Compare insane adjectiveOf unsound mindStupid and silly
(Definition of mad adjective (MENTALLY ILL) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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