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English definition of “rational”

rational

adjective    /ˈræʃ·ə·nəl/
showing clear thought or reason: a rational decision Obviously, he wasn’t rational. rationally    /ˈræʃ·ə·nəl·i/ adverb [not gradable] It’s hard to behave rationally at such times.
(Definition of rational adjective from the Cambridge Academic Content Dictionary © Cambridge University Press)
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