rea·​son | \ ˈrē-zᵊn How to pronounce reason (audio) \

Definition of reason

 (Entry 1 of 2)

1a : a statement offered in explanation or justification gave reasons that were quite satisfactory
b : a rational ground or motive a good reason to act soon
c : the thing that makes some fact intelligible : cause the reason for earthquakes the real reason why he wanted me to stay— Graham Greene
d : a sufficient ground of explanation or of logical defense especially : something (such as a principle or law) that supports a conclusion or explains a fact the reasons behind her client's action
2a(1) : the power of comprehending, inferring, or thinking especially in orderly rational ways : intelligence
(2) : proper exercise of the mind
(3) : sanity
b : the sum of the intellectual powers
3 archaic : treatment that affords satisfaction
in reason within reason
: within reasonable limits
with reason
: with good cause


reasoned; reasoning\ ˈrēz-​niŋ How to pronounce reason (audio) , ˈrē-​zᵊn-​iŋ \

Definition of reason (Entry 2 of 2)

intransitive verb

1 : to use the faculty of reason so as to arrive at conclusions
2a : to talk with another so as to influence actions or opinions can't reason with them
b obsolete : to take part in conversation, discussion, or argument

transitive verb

1 : to discover, formulate, or conclude by the use of reason a carefully reasoned analysis
2 : to persuade or influence by the use of reason
3 archaic : to justify or support with reasons

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Other Words from reason


reasoner \ ˈrēz-​nər How to pronounce reason (audio) , ˈrē-​zᵊn-​ər \ noun

Choose the Right Synonym for reason


think, cogitate, reflect, reason, speculate, deliberate mean to use one's powers of conception, judgment, or inference. think is general and may apply to any mental activity, but used alone often suggests attainment of clear ideas or conclusions. teaches students how to think cogitate implies deep or intent thinking. cogitated on the mysteries of nature reflect suggests unhurried consideration of something recalled to the mind. reflecting on fifty years of married life reason stresses consecutive logical thinking. able to reason brilliantly in debate speculate implies reasoning about things theoretical or problematic. speculated on the fate of the lost explorers deliberate suggests slow or careful reasoning before forming an opinion or reaching a conclusion or decision. the jury deliberated for five hours

Examples of reason in a Sentence

Noun I gave a reason for my absence. Is there a reason for your strange behavior? There is a reason why they don't want to come. I can't give you the report for the simple reason that it isn't yet finished. She explained her reasons for deciding to change jobs. He wanted to know the reason for their decision. Give me one good reason why I should believe you. For obvious reasons, we can't do that yet. For reasons of space, some of the charts and graphs have been omitted from the article. She resigned for personal reasons. Verb He lost the ability to reason. He reasoned that both statements couldn't be true. She reasoned that something must be wrong.
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Recent Examples on the Web: Noun But the Senate leader believes there’s ample reason to break the norm this time. George Skelton, Los Angeles Times, "Column: Drought is upon us. California’s Senate leader has a plan to keep it from becoming a crisis," 5 Apr. 2021 Women don’t need a justification for shaving, or for not shaving, but if someone’s looking for a reason to skip it, taking care of a baby is pretty much the best one. Elizabeth Logan, Glamour, "Katy Perry Showed Off Her Leg Hair on American Idol," 5 Apr. 2021 In his other start at left tackle, in Cleveland, well, there’s a reason Myles Garrett is a frontrunner for 2020 Defensive MVP. Jim Ayello, The Indianapolis Star, "Insider: Le’Raven Clark isn’t Anthony Castonzo but he’s a serviceable stopgap at left tackle," 5 Apr. 2021 And all this for one very bad reason: so that Donald J. Trump could retain power. Matt Labash, The New Republic, "An Epic Debate on Trump and True Evangelicalism," 5 Apr. 2021 The biggest reason schools are using hybrid learning is the need for distancing. Kristen Taketa, San Diego Union-Tribune, "Beyond just reopening schools, many parents want full-time in-person learning," 4 Apr. 2021 That bill is only done -- passed for one reason, because Joe Biden won Georgia and the two senators won Georgia. ABC News, "'This Week' Transcript 4-4-21: Lt. Gen. Russel Honoré (Ret.), Sen. Roy Blunt, Sec. Pete Buttigieg," 4 Apr. 2021 Border Patrol vehicles prowl the terrain, a big reason the migrants had placed their lives in the hands of smugglers — at a going rate of $7,500 to $10,000 each — to help penetrate the American fortress. New York Times, "A Car Crash in the California Desert: How 13 Died Riding in One S.U.V.," 4 Apr. 2021 Perhaps only Tolkien, with his immense intelligence and creativity, could have persuaded Lewis that his reason and imagination might become allies in the act of faith. Joseph Loconte, National Review, "How C. S. Lewis Accepted Christianity," 4 Apr. 2021 Recent Examples on the Web: Verb Without the tools to reason about mistakes a model is making in the wild, teams are investing a massive amount of money in the data science laboratory but essentially flying blind in the real world. Aparna Dhinakaran, Forbes, "Why Business Executives Should Be Hip To ML Tools," 5 Apr. 2021 However, remembering the Easter story and recognizing the significant strides made in combatting the coronavirus pandemic has given her and many others reason to look to the future. Brieanna J. Frank, The Arizona Republic, "'Hope is on the uptick': Phoenix-area clergy preach message of renewal for second pandemic Easter," 4 Apr. 2021 Just don’t try to reason the Ship of Theseus conundrum with it. Nina Huang,, "WandaVision merch alert! Get your exclusive first look at new tees, Funko Pops, and more," 8 Mar. 2021 She is exhausted by the constant attempts to reason with the void of an algorithm. New York Times, "Why Is Facebook Rejecting These Fashion Ads?," 11 Feb. 2021 As Lee angrily tries to reason with Delores (and keep everyone else from coming in after her), James can’t hide his look of surprise. Justin Curto, Vulture, "Below Deck Recap: Off the Deep End," 4 Jan. 2021 But thankfully, enough reasonable, common-sense voting adults still exist to reason beyond superficial fundraising benchmarks established by this gawd-awful insatiable quest (and love) for money. Mike Masterson, Arkansas Online, "MASTERSON ONLINE: Money taints politics," 26 Dec. 2020 This remains a huge mystery, and the new research hasn’t spoken to it enough for scientists to reason a surefire next step. Caroline Delbert, Popular Mechanics, "The Black Hole Information Paradox Is Just About Solved," 26 Nov. 2020 For all their philosophizing, Jason and Quentin and their father cannot reason their way out of evil and toward goodness. Casey Cep, The New Yorker, "William Faulkner’s Demons," 23 Nov. 2020

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


13th century, in the meaning defined at sense 1a


15th century, in the meaning defined at intransitive sense 2b

History and Etymology for reason


Middle English resoun, from Anglo-French raisun, from Latin ration-, ratio "reckoning, calculation, explanation," from reri "to calculate, think;" probably akin to Goth rathjo "account, explanation"

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Learn More about reason

Time Traveler for reason

Time Traveler

The first known use of reason was in the 13th century

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Statistics for reason

Last Updated

7 Apr 2021

Cite this Entry

“Reason.” Dictionary, Merriam-Webster, Accessed 10 Apr. 2021.

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More Definitions for reason



English Language Learners Definition of reason

 (Entry 1 of 2)

: a statement or fact that explains why something is the way it is, why someone does, thinks, or says something, or why someone behaves a certain way
: a fact, condition, or situation that makes it proper or appropriate to do something, feel something, etc.
: the power of the mind to think and understand in a logical way



English Language Learners Definition of reason (Entry 2 of 2)

: to think in a logical way
: to form (a conclusion or judgment) by thinking logically


rea·​son | \ ˈrē-zᵊn How to pronounce reason (audio) \

Kids Definition of reason

 (Entry 1 of 2)

1 : a statement given to explain a belief or an act My parents gave a reason for my absence.
2 : a fact that makes something right or fair to do I have reasons for what I did.
3 : cause entry 1 sense 1 The child wanted to know the reason for rain.
4 : the power to think and understand in a logical way
5 : a fair and sensible way of thinking about something He won't listen to reason.


reasoned; reasoning

Kids Definition of reason (Entry 2 of 2)

1 : to think in a logical way
2 : to talk with another in a sensible way so as to influence his or her actions or opinions “It's a fear you can't be … reasoned out of.”— Kate DiCamillo, Because of Winn-Dixie
3 : to state or ask logically How, I reasoned, could such a thing happen?



Legal Definition of reason

1 : an underlying ground, justification, purpose, motive, or inducement required to provide reasons for the termination in writing
2a : the faculty of comprehending, inferring, or distinguishing especially in a fair and orderly way
b : the proper and sane exercise of the mind

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