rational

adjective
ra·tio·nal | \ˈrash-nəl, ˈra-shə-nᵊl\

Definition of rational 

(Entry 1 of 2)

1a : having reason or understanding

b : relating to, based on, or agreeable to reason : reasonable a rational explanation rational behavior

2 : involving only multiplication, division, addition, and subtraction and only a finite number of times

3 : relating to, consisting of, or being one or more rational numbers a rational root of an equation

rational

noun

Definition of rational (Entry 2 of 2)

: something rational specifically : rational number

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Other Words from rational

Adjective

rationally adverb
rationalness noun

Examples of rational in a Sentence

Adjective

human beings are rational creatures insisted there was a rational explanation for the strange creaking noises and that there were no such things as ghosts

Recent Examples on the Web: Adjective

Always remember that without using rational thought, your success is entirely a matter of chance or luck. Paul C. Brunson, USA TODAY, "Paul C. Brunson: These 3 books are the best ever written on self-control and willpower," 5 July 2018 In a geopolitical climate that’s yearning for rational adults, the nostalgia for Nelson Mandela is potent. Kaitlin Menza, Town & Country, "Seeking Nelson Mandela in South Africa," 18 July 2017 Just because young white men are experiencing hurt feelings does not make those hurt feelings rational, or reasonable, or a sound basis for policy-making. Laurie Penny, Longreads, "Peterson’s Complaint," 12 July 2018 Some people would attribute her assessment to rational thought. Al Haas, Philly.com, "A roadster you just can't get over: The Pontiac Solstice | Al Haas," 22 June 2018 Matthew Yglesias of Vox is equally skeptical of Trump’s ability to pursue a rational policy, arguing that Trump’s North Korea policy amounts to theatrical antics meant to garner positive press. Jeet Heer, The New Republic, "Is This the Dawn of a New Era of Nuclear Proliferation?," 15 May 2018 For a few, a rejection of higher education might seem rational. Jeffrey Selingo, The Atlantic, "The False Promises of Worker Retraining," 8 Jan. 2018 Government health studies show that people who have recently eaten and are not feeling hungry are more likely to make rational decisions. Paul C. Brunson, USA TODAY, "Paul C. Brunson: These 3 books are the best ever written on self-control and willpower," 5 July 2018 And a rational way is not locking children up in detention centers or separating them from their mothers. Luke Darby, GQ, "What the Hell, Bernie Sanders?," 28 June 2018

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

Adjective

14th century, in the meaning defined at sense 1a

Noun

1601, in the meaning defined above

History and Etymology for rational

Adjective

Middle English racional, from Anglo-French racionel, from Latin rationalis, from ration-, ratio

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Statistics for rational

Last Updated

9 Oct 2018

Look-up Popularity

Time Traveler for rational

The first known use of rational was in the 14th century

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More Definitions for rational

rational

adjective

English Language Learners Definition of rational

: based on facts or reason and not on emotions or feelings

: having the ability to reason or think about things clearly

rational

adjective
ra·tio·nal | \ˈra-shə-nᵊl \

Kids Definition of rational

1 : having the ability to reason Humans are rational creatures.

2 : based on or showing reason rational thinking a rational decision

Other Words from rational

rationally adverb

rational

adjective
ra·tio·nal | \ˈrash-nəl, -ən-ᵊl \

Medical Definition of rational 

1a : having reason or understanding

b : relating to, based on, or agreeable to reason a rational explanation rational behavior

2 : using medical treatments based on reason or general principles used especially of an ancient school of physicians — compare empirical sense 1a

Other Words from rational

rationally \ \ adverb

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rational

adjective
ra·tio·nal | \ˈra-shə-nəl \

Legal Definition of rational 

1 : having reason or understanding

2 : relating to, based on, or guided by reason, principle, fairness, logic, a legitimate state interest, or a consideration of fact age distinctions are not subject to strict scrutiny, but they must have a rational relationship to a legitimate state interestIn re J. M., 642 A.2d 1062 (1994)

Other Words from rational

rationality \ˌra-shə-ˈna-lə-tē \ noun
rationally adverb

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Comments on rational

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