Simple Definition of rational

: based on facts or reason and not on emotions or feelings

: having the ability to reason or think about things clearly
Full Definition of rational
1 a : having reason or understanding b : relating to, based on, or agreeable to reason : reasonable <a rational explanation> <rational behavior>
2 : involving only multiplication, division, addition, and subtraction and only a finite number of times
3 : relating to, consisting of, or being one or more rational numbers <a rational root of an equation>
Examples of rational
<human beings are rational creatures>
<insisted there was a rational explanation for the strange creaking noises and that there were no such things as ghosts>
Origin of rational
Middle English racional, from AngloFrench racionel, from Latin rationalis, from ration, ratio
First Known Use: 14th century
rational
Definition of rational
: something rational; specifically : rational number
1606
First Known Use of rational
1606
Medical Dictionary
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Thesaurus: All synonyms and antonyms for "rational" Medical Dictionary: Definition of "rational" Spanish Central: Translation of "rational" Nglish: Translation of "rational" for Spanish speakers Britannica English: Translation of "rational" for Arabic speakers
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