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 Restoring rationality and a sense of responsibility to all Americans will take decades. Robert G. Eccles, Forbes, 5 July 2022 But love remains a profound exception to humanity’s trend toward rationality. Benjamin Kaveladze, The Conversation, 12 July 2022 Liberal internationalism is a product of the fin de siècle, when Progressive thinkers, activists, and policymakers across the political spectrum believed that rationality could achieve mastery over human affairs. Daniel Bessner, Harper’s Magazine , 22 June 2022 Really, all a rationality standard would ask is that states have a reason. Emily Cooke, The New Republic, 6 May 2022 The hypothetical water passed the brim after the initial wave of the pandemic when rationality overtook the incumbent mindset. Seemant Sehgal, Forbes, 14 Apr. 2022 One person is a vehement defender; the other is, under the guise of rationality, trying to catch her somehow tricking us. Jenny Singer, Glamour, 24 May 2022 Scientist and writer Camilla Pang explains what the rationality of science showed her about making better decisions, processing feedback, and feeling like an outlier. Simran Sethi, Wired, 26 Feb. 2022 Thompson wants to examine why Shylock abandons rationality, insists on a moral wrong and then — this is the sticking point — refuses to relent. New York Times, 3 Feb. 2022 See More

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.

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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Last Updated

2 Aug 2022

Cite this Entry

“Rationality.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rationality. Accessed 7 Aug. 2022.

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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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