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English definition of “irrational”

irrational

adjective     /ɪˈræʃənəl/
Irrational feelings and actions are based on your emotions and not on good reasons: irrational behaviour an irrational fear of flyingOf unsound mindStupid and silly
irrationality     /ɪˌræʃənˈæləti/ noun [U] irrationally adverb
(Definition of irrational adjective from the Cambridge Learner's Dictionary © Cambridge University Press)

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