ra·​tio·​nal·​i·​ty | \ ˌra-shə-ˈna-lə-tē How to pronounce rationality (audio) \
plural rationalities

Definition of rationality

1 : the quality or state of being rational
2 : the quality or state of being agreeable to reason : reasonableness
3 : a rational opinion, belief, or practice usually used in plural

Examples of rationality in a Sentence

Recent Examples on the Web Washington isn’t a city particularly known for its rationality. Philip Elliott, Time, "The Security Perimeter Around the Capitol Starts to Recede — and Washington Feels a Little More Normal," 25 Mar. 2021 Though not enough, fortunately, to diminish her rationality, her courage, her sense of obligation to seek justice for a woman so treated. Dorothy Rabinowitz, WSJ, "‘Nevenka: Breaking the Silence’ Review: Speaking Up in Spain," 4 Mar. 2021 In both cases, intelligence and rationality are championed as the ultimate validations, while stupidity and insanity are the ultimate put-downs. Andrew Pulrang, Forbes, "How Giving Up Ableist Insults Can Help Heal Our Politics," 24 Feb. 2021 Better, perhaps, to inject some rationality into the event, especially as the Brood X cicada relates to our yards and gardens. Washington Post, "The cicadas are coming. But gardeners need not panic.," 31 Mar. 2021 And though his hero was rationality embodied, Holmes creator Arthur Conan Doyle himself believed in worlds beyond this world and the possibility of communicating with them. Robert Lloyd, Los Angeles Times, "Sherlock’s a mess. Watson’s a snob. The youngest players of ‘The Irregulars’? Extraordinary," 26 Mar. 2021 Prioritize simplicity in everything and rationality over office politics. François Cazor, Forbes, "How To Build Culture And Values At A Bootstrapped Company," 18 Mar. 2021 The comity between faith and scientific rationality that had previously existed began to fracture after the Civil War. Michael Luo, The New Yorker, "The Wasting of the Evangelical Mind," 4 Mar. 2021 Humans as a species are very bad at applying rationality to their own emotions. Megan Greenwell, Wired, "Help! I’m Sneaking Into My Office. Is This So Wrong?," 3 Mar. 2021

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

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First Known Use of rationality

1628, in the meaning defined at sense 1

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Time Traveler for rationality

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The first known use of rationality was in 1628

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Statistics for rationality

Last Updated

16 Apr 2021

Cite this Entry

“Rationality.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rationality. Accessed 7 May. 2021.

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More Definitions for rationality


ra·​tio·​nal·​i·​ty | \ ˌrash-ə-ˈnal-ət-ē How to pronounce rationality (audio) \
plural rationalities

Medical Definition of rationality

1 : the quality or state of being rational
2 : the quality or state of being agreeable to reason

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