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English definition of “insanity”

insanity

noun [U]     /ɪnˈsænəti/
MENTAL ILLNESS serious mental illnessMental and psychiatric disorders
STUPID a very stupid thing to do: It would be insanity to expand the business at the moment.Stupid and sillyOf unsound mind
(Definition of insanity noun from the Cambridge Learner's Dictionary © Cambridge University Press)

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