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English definition of “rational”

rational

adjective uk   /ˈræʃ.ən.əl/ us  
C1 showing clear thought or reason: He was too upset to be rational. a rational course of action/argument/explanationLogic and reason
rationality
noun [U] uk   /ˌræʃ.ənˈæl.ɪ.ti/ us    /-ə.t̬i/
Mind and personalityScience of psychology and psychoanalysis
(Definition of rational from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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