reason

1 of 2

noun

rea·​son ˈrē-zᵊn How to pronounce reason (audio)
1
a
: 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 stayGraham 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
2
a(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

reason

2 of 2

verb

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

intransitive verb

1
: to use the faculty of reason so as to arrive at conclusions
2
a
: 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
reasoner
ˈrēz-nər How to pronounce reason (audio)
ˈrē-zᵊn-ər
noun
Phrases
in reason within reason
: within reasonable limits
with reason
: with good cause
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.
Recent Examples on the Web
Noun
One of the main reasons for the United States dropping out of the top 20 is the overall unhappiness of younger people, according to the report. Jon Haworth, ABC News, 20 Mar. 2024 There’s a reason why a package of Netflix and Max is available through Verizon and not Netflix. Georg Szalai, The Hollywood Reporter, 20 Mar. 2024 In 2024, 46 states will offer early, in-person voting, and 36 will offer the option to vote by mail without having to cite a reason. Benjamin Oreskes, Los Angeles Times, 20 Mar. 2024 Crossroads makes big impact in Greater Cincinnati Crossroads, with about 30,000 members, is a big reason why. Dan Horn, The Enquirer, 20 Mar. 2024 But there’s a reason the procedure is rarely used: All 100 senators hardly ever agree. Jacob Bogage, Washington Post, 20 Mar. 2024 The Toronto native admitted that maintaining the perfect record wasn’t the reason the team felt extra pressure to win. Joseph Dycus, The Mercury News, 20 Mar. 2024 But wealthy citizens are increasingly considering a life across the Atlantic, with an unappealing showdown between Joe Biden and Donald Trump being labeled as the reason. Ryan Hogg, Fortune Europe, 20 Mar. 2024 And there’s good reason to believe that Russia takes NATO very seriously, even if some U.S. politicians don’t. Anna Mulrine Grobe, The Christian Science Monitor, 19 Mar. 2024
Verb
LLMs weren't designed to reason, so researchers found that results improve a great deal when a prompt's question is followed by an example—including each step—of how to correctly solve a similar problem. David Berreby, Scientific American, 20 Feb. 2024 If developing a bomb was so hard for their own scientists, the Nazis appear to have reasoned, how could the degenerate Allies ever do it? Claudia Roth Pierpont, The New Yorker, 19 Feb. 2024 But a planned October trip was canceled by the mayor, who reasoned his time was better off spent dealing with the immediate needs in Chicago and instead sending a delegation of city officials in his place. Michael Lee, Fox News, 7 Feb. 2024 After reports of early earthquake relief supplies being stolen by the Somoza regime in Nicaragua, Clemente decided to deliver the next plane of earthquake supplies himself, perhaps reasoning that government thieves wouldn’t dare steal from Roberto Clemente in the flesh. Stephen Rodrick, Variety, 8 Mar. 2024 Robin, listening in, reasoned that someone had broken into Steve’s parents’ home to hold them up for a little cash. Charles Bethea, The New Yorker, 7 Mar. 2024 By delving deeply into users' mental models and reasoning patterns, Momentum Design Lab seamlessly integrates AI with human strengths, such as emotion and creativity. Chris Gallagher, USA TODAY, 4 Mar. 2024 In 1981, the Japanese Ministry of International Trade and Industry set aside $850 million for the Fifth Generation computer project, with the goal of developing thinking machines that will reason like humans. Gil Press, Forbes, 25 Feb. 2024 The board reasoned that the decision by the worker — identified as Antonio Morales — to display the BLM acronym on the apron was a direct response to racial discrimination complaints within the store and is protected under federal law. Anne D'innocenzio, Quartz, 21 Feb. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'reason.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Noun

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"

First Known Use

Noun

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

Verb

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

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

Dictionary Entries Near reason

Cite this Entry

“Reason.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reason. Accessed 29 Mar. 2024.

Kids Definition

reason

1 of 2 noun
rea·​son ˈrēz-ᵊn How to pronounce reason (audio)
1
a
: a statement given to explain a belief or act
gave a reason for my absence
b
: a good basis
reasons for thinking life may exist on other planets
c
: the thing that makes some fact understandable : cause
wanted to know the reason for earthquakes
2
a
: the power to think : intelligence
b
: a sound mind

reason

2 of 2 verb
reasoned; reasoning ˈrēz-niŋ How to pronounce reason (audio)
-ᵊn-iŋ
1
: to talk with another in order to cause a change of mind
reason with someone
2
a
: to use the power of reason
b
: to state or conclude by use of reason
reasoned that both statements couldn't be true

Legal Definition

reason

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

More from Merriam-Webster on reason

Last Updated: - Updated example sentences
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