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1

rational

play
adjective ra·tio·nal \ˈrash-nəl, ˈra-shə-nəl\

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of rational

  1. 1 a :  having reason or understanding b :  relating to, based on, or agreeable to reason :  reasonable <a rational explanation> <rational behavior>

  2. 2 :  involving only multiplication, division, addition, and subtraction and only a finite number of times

  3. 3 :  relating to, consisting of, or being one or more rational numbers <a rational root of an equation>

rationally

adverb

rationalness

noun

Examples of rational in a sentence

  1. <human beings are rational creatures>

  2. <insisted there was a rational explanation for the strange creaking noises and that there were no such things as ghosts>



Origin and Etymology of rational

Middle English racional, from Anglo-French racionel, from Latin rationalis, from ration-, ratio


First Known Use: 14th century


2

rational

noun ra·tio·nal

Definition of rational

  1. :  something rational; specifically :  rational number



1606

First Known Use of rational

1606


RATIONAL Defined for Kids

rational

play
adjective ra·tio·nal \ˈra-shə-nəl\

Definition of rational for Students

  1. 1 :  having the ability to reason <Humans are rational creatures.>

  2. 2 :  based on or showing reason <rational thinking> <a rational decision>

rationally

adverb



Medical Dictionary

rational

play
adjective ra·tio·nal \ˈrash-nəl, -ən-əl\

Medical Definition of rational

  1. 1a:  having reason or understandingb:  relating to, based on, or agreeable to reason <a rational explanation> <rational behavior>

  2. 2:  using medical treatments based on reason or general principles—used especially of an ancient school of physicians; compare empirical 1a

rationally

\-ē\play adverb



Law Dictionary

rational

play
adjective ra·tio·nal \ˈra-shə-nəl\

Legal Definition of rational

  1. 1 :  having reason or understanding

  2. 2 :  relating to, based on, or guided by reason, principle, fairness, logic, a legitimate state interest, or a consideration of fact <age distinctions are not subject to strict scrutiny, but they must have a rational relationship to a legitimate state interest — In re J. M., 642 A.2d 1062 (1994)>

rationality

\ˌra-shə-ˈna-lə-tē\ play noun

rationally

adverb




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