ra·​tio·​nal | \ ˈrash-nəl How to pronounce rational (audio) , ˈra-shə-nᵊl \

Definition of rational

 (Entry 1 of 2)

1a : 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



Definition of rational (Entry 2 of 2)

: something rational specifically : rational number

Other Words from rational


rationally adverb
rationalness noun

Examples of rational in a Sentence

Adjective 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
Recent Examples on the Web: Adjective Investors became concerned that the acquisition signals a change of strategy, a deterioration in future prospects, or a departure from management's rational capital allocation strategy. Jacob Wolinsky, Forbes, 13 May 2022 Some chapters are responses to a position those familiar with young children will recognize, of a rational being attempting to reason with an irrational one. Barbara Spindel, The Christian Science Monitor, 12 May 2022 The choice, the show asserted, feels less like a rational Court judgment and more like a fallacious argument that a fringe Facebook group might circulate as fact. Amanda Wicks, The Atlantic, 8 May 2022 But Amezcua-Patino said knowing the law and having factual knowledge is not the same as having a rational understanding. Jimmy Jenkins, The Arizona Republic, 3 May 2022 There are many ways to go around bringing rational goals. David Marchesephoto Illustration By Bráulio Amado, New York Times, 22 Apr. 2022 But, to Benda, the true betrayal of Barrès and Maurras was their refusal to engage in rational thought. James Mcauley, The New Yorker, 22 Apr. 2022 There's no room for rational thought in this space. Matt Eppers, USA TODAY, 18 Apr. 2022 The reader soon fears for each of Bjerke’s investigators: a mystery novelist, an ardent occultist, a highly rational psychiatrist, a fearless and beautiful actress and a just-the-facts amateur detective. Washington Post, 6 Apr. 2022 Recent Examples on the Web: Noun Empirical inquiry—often considered strictly a province of the rational—can also be fueled by fervent belief. Faith Hill, The Atlantic, 6 May 2022 But other states and cities are taking their positive revenues as a rational for deep tax cuts. Richard Mcgahey, Forbes, 14 Apr. 2022 The gas supply in 1974 was reported to have bottomed out at only about 20% below normal, but drivers acted about 50% below rational. Los Angeles Times, 22 Mar. 2022 In the book, Starhawk defines magic as awakening deeper levels of consciousness beyond the rational. WSJ, 8 Dec. 2021 Darkside is something entirely distinct, a surreal form of magic at war with the rational. Washington Post, 23 July 2021 In her 2017 essay, Khan also pointed to platforms’ creating incentives for companies to favor growth over profits, which ostensibly makes predatory pricing rational. Jessica Melugin, National Review, 22 June 2021 Advocates for race-conscious admissions accept the diversity rational as an article of faith. Michael T. Nietzel, Forbes, 1 June 2021 Much of the rational of the calls to expand the court came from the fact that former President Donald Trump had appointed three justices, shifting the balance. Peter Suciu, Forbes, 15 Apr. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rational.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of rational


14th century, in the meaning defined at sense 1a


1601, in the meaning defined above

History and Etymology for rational


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

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The first known use of rational was in the 14th century

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Last Updated

18 May 2022

Cite this Entry

“Rational.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rational. Accessed 26 May. 2022.

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More Definitions for rational


ra·​tio·​nal | \ ˈra-shə-nᵊl How to pronounce rational (audio) \

Kids Definition of rational

1 : having the ability to reason Humans are rational creatures.
2 : based on or showing reason rational thinking a rational decision

Other Words from rational

rationally adverb


ra·​tio·​nal | \ ˈrash-nəl, -ən-ᵊl How to pronounce rational (audio) \

Medical Definition of rational

1a : having reason or understanding
b : relating to, based on, or agreeable to reason a rational explanation rational behavior
2 : using medical treatments based on reason or general principles used especially of an ancient school of physicians — compare empirical sense 1a

Other Words from rational

rationally \ -​ē How to pronounce rational (audio) \ adverb


ra·​tio·​nal | \ ˈra-shə-nəl How to pronounce rational (audio) \

Legal Definition of rational

1 : having reason or understanding
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 interestIn re J. M., 642 A.2d 1062 (1994)

Other Words from rational

rationality \ ˌra-​shə-​ˈna-​lə-​tē How to pronounce rational (audio) \ noun
rationally adverb

More from Merriam-Webster on rational

Nglish: Translation of rational for Spanish Speakers

Britannica English: Translation of rational for Arabic Speakers


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