rational

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

|Updated on: 14 Aug 2018

Examples: rational in a Sentence

Definition of rational

1 a : 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

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rationally

adverb

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rationalness

noun

See rational defined for English-language learners

See rational defined for kids

Examples of rational in a Sentence

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 of rational from the Web

But other Europeans should not be too haughty about Germany’s debate, for their own rows on asylum are barely more rational.

— The Economist, "How policy debates in Europe become untethered from reality," 12 July 2018
The only rational explanation is that Baltimore’s front office is terrified of the fans revolting and abandoning Camden Yards in droves should Machado get dealt.

— si.com staff, SI.com, "Quarter-Season Roundtable: Are the Dodgers Finished? Are the Braves Legitimate?," 17 May 2018
Reformers had been calling for more sensible clothing for women since the 1850s, when the newspaper editor Amelia Bloomer wore the baggy trousers that critics named after her, but rational arguments hadn’t made much headway.

— aaron gilbreath, Longreads, "The Wheel, the Woman, and the Human Body," 6 July 2018
Hatred and fear never operate within rational boundaries.

— amro ali, Time, "Denmark’s “Ghetto” Policies Are an Ominous Sign That Liberal Europe Is Starting to Unravel at the Seams," 3 July 2018
None of this is to say any rational person would turn down a chance to add James to a roster.

— bryce miller, sandiegouniontribune.com, "Memo to Luke Walton: Here's comes LeBron ... and all that comes with it," 2 July 2018
The fair question is why any rational person or business that can move would stay in New Jersey.

— the editorial board, WSJ, "New Jersey’s Tax Gift to Florida," 1 July 2018
What Waters grasped was that the anger being expressed was a rational response to injustice.

— rebecca traister, The Cut, "Summer of Rage," 29 June 2018
And more importantly, how can the rational citizens of the internet help snap them back to a reality devoid of lizard people and shadowy baby-stealing organizations?

— emma grey ellis, WIRED, "Here’s One Way to Reform an Internet Conspiracy Theorist," 27 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.

Origin and Etymology of rational

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

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First Known Use: 14th century

in the meaning defined at sense 1a

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rational Synonyms

rational

noun

Definition of rational

: something rational; specifically : rational number

First Known Use of rational

1601

in the meaning defined above

See Words from the same year

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RATIONAL Defined for English Language Learners

rational

adjective

Definition of rational for English Language Learners

: based on facts or reason and not on emotions or feelings
: having the ability to reason or think about things clearly

RATIONAL Defined for Kids

rational

adjective ra·tio·nal \ ˈra-shə-nᵊl \

Definition of rational for Students

1 : having the ability to reason

Humans are rational creatures.

2 : based on or showing reason

rational thinking

a rational decision

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rationally

adverb

Medical Dictionary

rational

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

medical Definition of rational

1 a : 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 1a

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rationally

play \-ē\ adverb

Law Dictionary

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 interest
—In re J. M., 642 A.2d 1062 (1994)

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