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 This, sadly, is one of those occasions, with BMW’s official confirmation of a car that rational market forces are set to deny us. Mike Duff, Car and Driver, 21 June 2022 Buying some time to think is a rational way to manage the flow of a conversation. Neil Senturia, San Diego Union-Tribune, 20 June 2022 Josh Minott was clearly reluctant to answer the question, to put himself out there and risk the wrath of the Twitter armchair masses, who are not always known to be kind or rational. Eric Walden, The Salt Lake Tribune, 15 June 2022 Following Hinman’s speech, Ripple met several times with key officials at the SEC, believing that rational minds would all agree on XRP’s status as something other than a security. Stu Alderoty, Fortune, 13 June 2022 Simply feeling your own presence while alone in a natural environment is a wonderful way to remember that—to tune into your own deeper nature, beyond the rational brain and monkey mind. Carolyn L. Todd, SELF, 8 June 2022 According to the Harvard Business Review, in a stressful situation—like a possibly once-in-a-lifetime archival sale—our brains react differently, forcing us to make reactionary decisions instead of thoughtful, rational ones. Liana Satenstein, Vogue, 7 June 2022 As various local experiments demonstrate, rational conversation about topics such as immigration isn’t impossible, even in the most unlikely places. Bill Mckibben, The New Yorker, 3 June 2022 But a rational discussion about the Space Launch System rocket and its payload, the Orion spacecraft, is impossible without considering its enormous expense, ongoing delays, and looming obsolescence. Eric Berger, Ars Technica, 25 Mar. 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

23 Jun 2022

Cite this Entry

“Rational.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rational. Accessed 3 Jul. 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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