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1

rational

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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

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>

ra·tio·nal·ly adverb
ra·tio·nal·ness noun

Examples of rational

  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 of rational

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


First Known Use: 14th century

Rhymes with rational


2

rational

noun ra·tio·nal

Definition of rational

  1. :  something rational; specifically :  rational number



1606

First Known Use of rational

1606


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

  3. ra·tio·nal·ly \-ē\play adverb





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