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 His rationale was a fierce adherence to prior Supreme Court precedent. Fortune, "The unsettled future of Supreme Court abortion cases," 30 June 2020 Taking down a statue of of Teddy Roosevelt -- whatever the subtleties of the arguments are, however justified is the rationale -- doesn't sound like a good idea, optically. The Washington Post, "Chatological Humor with Gene Weingarten," 23 June 2020 Governor Kate Brown shared more details Thursday about her plans to require most Oregonians to wear face covering and her rationale for allowing the state’s largest county to reopen as coronavirus cases surge. oregonlive, "Gov. Kate Brown explains her mask requirement, reopening rationale; health official admits error," 18 June 2020 In June 2018, then-Secretary of Homeland Security Kirstjen Nielsen released a second memo outlining the administration’s rationale for ending the program after a federal court in D.C. held that DHS’s decision could be reviewed by the courts. Matt Ford, The New Republic, "Trump’s Ineptitude Keeps Dream Alive for DACA Recipients," 18 June 2020 Therefore, there is a strong rationale for homeownership in the peripheries. Anuj Puri, Quartz India, "The work-from-home culture could change how Indians buy homes," 16 June 2020 The judge rejected Molina’s claims in an order that didn’t explain her rationale. Isaac Arnsdorf, ProPublica, "How Rich Investors, Not Doctors, Profit From Marking Up ER Bills," 12 June 2020 The rationale behind municipal income taxes is this: Employees avail themselves to city services – police, fire and EMS services, for example -- while earning their income in the taxing city. Peter Krouse, cleveland, "Working from home trend could imperil some Northeast Ohio communities," 9 June 2020 But the three Fourth Circuit judges who heard the case — all nominated by Republican presidents — repeatedly questioned Mosier about the Supreme Court’s finding that there is a plausible rationale to support the travel ban. Denise Lavoie, BostonGlobe.com, "Court orders dismissal of Trump Muslim travel ban challenges," 8 June 2020

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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Time Traveler for rationale

Time Traveler

The first known use of rationale was in 1657

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Last Updated

6 Jul 2020

Cite this Entry

“Rationale.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rationale. Accessed 6 Jul. 2020.

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More Definitions for rationale


How to pronounce rationale (audio)

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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