1

rational

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

Definition of rational

  1. 1a :  having reason or understandingb :  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

1601

First Known Use of rational

1601


RATIONAL Defined for English Language Learners

1

rational

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

Definition of rational for English Language Learners

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

  • : having the ability to reason or think about things clearly


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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