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rational

[ rash-uh-nl, rash-nl ]
/ ˈræʃ ə nl, ˈræʃ nl /
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See synonyms for: rational / rationally / rationalness on Thesaurus.com

adjective
noun
Mathematics. rational number.
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Origin of rational

First recorded in 1350–1400; Middle English racional, from Latin ratiōnālis, equivalent to ratiōn- (stem of ratiō ) reason + -ālis -al1

synonym study for rational

6. See reasonable.

OTHER WORDS FROM rational

WORDS THAT MAY BE CONFUSED WITH rational

rational , reasonable (see synonym study at reasonable)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use rational in a sentence

British Dictionary definitions for rational

rational
/ (ˈræʃənəl) /

adjective
using reason or logic in thinking out a problem
in accordance with the principles of logic or reason; reasonable
of sound mind; sanethe patient seemed quite rational
endowed with the capacity to reason; capable of logical thoughtman is a rational being
maths expressible as a ratio of two integers or polynomialsa rational number; a rational function
noun
maths a rational number

Derived forms of rational

rationally, adverbrationalness, noun

Word Origin for rational

C14: from Latin ratiōnālis, from ratiō reason
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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