rational

1 of 2

adjective

ra·​tio·​nal ˈrash-nəl How to pronounce rational (audio)
ˈra-shə-nᵊl
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
rationally adverb
rationalness noun

rational

2 of 2

noun

: something rational
specifically : rational number

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
Logical fallacies are quite similar to cognitive biases which can be defined as the systematic departure from rational thinking. Christine Comaford, Forbes, 2 Mar. 2024 The rational part of me knows that the conjunction of Irena Rey’s publication and the shift in the nation’s politics is a coincidence. Nathan Jeffers, Hazlitt, 28 Feb. 2024 Emotions unleashed by unforeseen circumstances can distort a person’s rational calculation of the cost of their actions—which can involve shame, say, or an estimation of the chances of getting caught—versus the benefits of the crime. Ingrid Wickelgren, Scientific American, 21 Feb. 2024 The version that will work for the people that will read the series as a completely rational story is that the tongue was found by the people of the village. Kate Aurthur, Variety, 19 Feb. 2024 Saying that something is a symbol does not rob it of rational significance. Adam Gopnik, The New Yorker, 19 Feb. 2024 By understanding these biases, investors can better navigate the psychological pitfalls of the market, leading to more informed and rational investment decisions. Dan Irvine, Forbes, 28 Feb. 2024 The current budget process is broken and with the challenges that now confront California, even beyond the $68 billion deficit, the time would be right to bring a more rational approach to state government spending. Jon Coupal, Orange County Register, 25 Feb. 2024 This emotional volatility in turn allows for calmer, more rational decision-making. Olivia Goldhill, STAT, 22 Feb. 2024
Noun
At the time the database had a little over 3 million elliptic curves over the rationals. Lyndie Chiou, Quanta Magazine, 5 Mar. 2024 Is there a set of points on that line, on the number line, which is larger than the natural numbers, larger than the rationals, but smaller than the whole line itself? Steven Strogatz, Quanta Magazine, 19 Apr. 2023 Empirical inquiry—often considered strictly a province of the rational—can also be fueled by fervent belief. Faith Hill, The Atlantic, 6 May 2022 But other states and cities are taking their positive revenues as a rational for deep tax cuts. Richard McGahey, Forbes, 14 Apr. 2022 The gas supply in 1974 was reported to have bottomed out at only about 20% below normal, but drivers acted about 50% below rational. Los Angeles Times, 22 Mar. 2022 In the book, Starhawk defines magic as awakening deeper levels of consciousness beyond the rational. WSJ, 8 Dec. 2021 Darkside is something entirely distinct, a surreal form of magic at war with the rational. Washington Post, 23 July 2021 In her 2017 essay, Khan also pointed to platforms’ creating incentives for companies to favor growth over profits, which ostensibly makes predatory pricing rational. Jessica Melugin, National Review, 22 June 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'rational.' 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

Adjective

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

First Known Use

Adjective

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

Noun

1601, in the meaning defined above

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

Dictionary Entries Near rational

Cite this Entry

“Rational.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rational. Accessed 18 Mar. 2024.

Kids Definition

rational

1 of 2 adjective
ra·​tio·​nal ˈrash-nəl How to pronounce rational (audio)
-ən-ᵊl
1
a
: having the ability to reason
rational beings
b
: relating to, based on, or showing reason : reasonable sense 2
rational behavior
2
: relating to or involving rational numbers
a rational fraction
rationally
adverb

rational

2 of 2 noun
: something rational
especially : rational number

Medical Definition

rational

adjective
ra·​tio·​nal ˈrash-nəl, -ən-ᵊl How to pronounce rational (audio)
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 sense 1a
rationally adverb

Legal Definition

rational

adjective
ra·​tio·​nal ˈra-shə-nəl How to pronounce rational (audio)
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)
rationality noun
rationally adverb

More from Merriam-Webster on rational

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