ra·​tio·​nale | \ ˌra-shə-ˈnal How to pronounce rationale (audio) \

Definition of rationale

1 : an explanation of controlling principles of opinion, belief, practice, or phenomena
2 : an underlying reason : basis

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Did You Know?

The word rationale appeared in the second half of the 17th century, just in time for the Age of Reason. It is based on the Latin ratio, which means "reason," and rationalis, which means "endowed with reason." At first, rationale meant "an explanation of controlling principles" ("a rationale of religious practices," for example), but soon it began to refer to the underlying reason for something (as in "the rationale for her behavior"). The latter meaning is now the most common use of the term. The English word ratio can also mean "underlying reason" (in fact, it had this meaning before rationale did), but in current use, that word more often refers to the relationship (in number, quantity, or degree) between things.

Examples of rationale in a Sentence

the rationale for starting the school day an hour later is that kids will supposedly get an extra hour of sleep

Recent Examples on the Web

The rationale for building fancier dorms and rolling out plush amenities is that doing so might entice prospective students—especially those who can afford to pay full tuition—in a competitive higher-education market. Joe Pinsker, The Atlantic, "The Age of the Comfy College Dorm," 29 Aug. 2019 The rationale for it is much weaker today because [labels are] making a lot more money. Billboard Staff, Billboard, "Revealed: Billboard's 2019 Top Music Lawyers Led by BTS Counsel Debbie White of Loeb & Loeb," 26 Aug. 2019 Its rationale, in the eyes of both parents and proponents, was broadly utilitarian: Camp functioned as a vehicle for moral instruction as much as recreation, because kids’ characters needed building. Mac Schwerin, Vox, "The case against summer camp," 16 Aug. 2019 Part of her rationale was that Mr. Epstein played a lucrative role recruiting new customers to JPMorgan’s private-banking division, which caters to ultrawealthy people and families, the six employees said. Emily Flitter, New York Times, "JPMorgan Kept Jeffrey Epstein as a Client Despite Internal Warnings," 8 Aug. 2019 Trump declared his Presidential campaign on June 16, 2015, citing the presence of Mexican rapists as part of his rationale. Jelani Cobb, The New Yorker, "How the Trail of American White Supremacy Led to El Paso," 6 Aug. 2019 When Barr inevitably pressed him on what, then, was his rationale, Mueller said his team was still formulating its reasoning. . Andrew C. Mccarthy, National Review, "How Mueller’s Lawyers Spun the OLC Guidance on Indicting a Sitting President," 28 July 2019 Mayor London Breed and City Attorney Dennis Herrera sent Gov. Gavin Newsom a letter Wednesday outlining their rationale for looking at buying PG&E electric equipment serving the city and asking to meet with him soon. J.d. Morris, SFChronicle.com, "San Francisco could soon make PG&E ‘attractive offer’ for power lines," 28 July 2019 Netflix famously does not disclose viewership numbers for most shows, so its rationale for canceling these particular series is unclear. Tyler Aquilina, EW.com, "Netflix cancels Designated Survivor and Tuca & Bertie," 25 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rationale.' 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 rationale

1657, in the meaning defined at sense 1

History and Etymology for rationale

Latin, neuter of rationalis

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Last Updated

13 Sep 2019

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Time Traveler for rationale

The first known use of rationale was in 1657

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English Language Learners Definition of rationale

somewhat formal : the reason or explanation for something


ra·​tio·​nale | \ ˌra-shə-ˈnal How to pronounce rationale (audio) \

Kids Definition of rationale

: a basic explanation or reason for something What is the rationale behind your decision?

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Comments on rationale

What made you want to look up rationale? Please tell us where you read or heard it (including the quote, if possible).


authorized for issue (as a bond)

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