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
: something rational
specifically
: rational number
Synonyms
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
Alex Zaragoza, Los Angeles Times, 15 Sep. 2023
In these early passages, the parent-child dynamic feels reversed; Georgie is strict and rational while Jason is petulant.
—Odie Henderson, BostonGlobe.com, 14 Sep. 2023
The emphasis on his rational and bureaucratic approach, however, glosses over an important source of Vollmer’s ideas: his work overseas at the turn of the century, crushing local resistance in the Philippine-American War.
—Jack McCordick, The New Republic, 13 Sep. 2023
Bonello instructively distinguishes between the rational business of the international narcotics trade and the sadistic, misogynist gangs in El Salvador, where an old-school patriarchy prevails.
—Deborah Bonello, Foreign Affairs, 22 Aug. 2023
This is one where time must pass before a rational decision is made.
—Ndaschel, oregonlive, 18 Aug. 2023
Despite the rational demands of the unions and guilds, studio bigwigs aren’t budging, and their staunch refusal to create a more equitable working environment underscores a big bad that even the worst MCU villain couldn’t rival: capitalism.
—Ineye Komonibo, refinery29.com, 29 Aug. 2023
Or maybe just sip it, that certainly seems more rational.
—Jonah Flicker, Robb Report, 21 Aug. 2023
More rational pricing and packaging is helping to slowly boost per-subscriber economics.
—Patrick Frater, Variety, 10 Aug. 2023
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
Advocates for race-conscious admissions accept the diversity rational as an article of faith.
—Michael T. Nietzel, Forbes, 1 June 2021
See More
Adjective
Bad Bunny isn’t interested in ‘clarifying anything’ to fans
Sept. 12, 2023
My own mom and sister, two people who are of sound and rational mind, used to be genuinely concerned that duendes were stealing our laundry.
—Alex Zaragoza, Los Angeles Times, 15 Sep. 2023
In these early passages, the parent-child dynamic feels reversed; Georgie is strict and rational while Jason is petulant.
—Odie Henderson, BostonGlobe.com, 14 Sep. 2023
The emphasis on his rational and bureaucratic approach, however, glosses over an important source of Vollmer’s ideas: his work overseas at the turn of the century, crushing local resistance in the Philippine-American War.
—Jack McCordick, The New Republic, 13 Sep. 2023
Bonello instructively distinguishes between the rational business of the international narcotics trade and the sadistic, misogynist gangs in El Salvador, where an old-school patriarchy prevails.
—Deborah Bonello, Foreign Affairs, 22 Aug. 2023
This is one where time must pass before a rational decision is made.
—Ndaschel, oregonlive, 18 Aug. 2023
Despite the rational demands of the unions and guilds, studio bigwigs aren’t budging, and their staunch refusal to create a more equitable working environment underscores a big bad that even the worst MCU villain couldn’t rival: capitalism.
—Ineye Komonibo, refinery29.com, 29 Aug. 2023
Or maybe just sip it, that certainly seems more rational.
—Jonah Flicker, Robb Report, 21 Aug. 2023
More rational pricing and packaging is helping to slowly boost per-subscriber economics.
—Patrick Frater, Variety, 10 Aug. 2023
Noun
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
Advocates for race-conscious admissions accept the diversity rational as an article of faith.
—Michael T. Nietzel, Forbes, 1 June 2021
See More
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
Phrases Containing rational
Dictionary Entries Near rational
Cite this Entry
“Rational.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rational. Accessed 29 Sep. 2023.
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Kids Definition
rational
1 of 2 adjective
ra·tio·nal
ˈrash-nəl 
-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
-ē
rational
2 of 2 noun
: something rational
especially
: rational number
Medical Definition
rational
adjective
ra·tio·nal
ˈrash-nəl, -ən-ᵊl
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
Legal Definition
rational
adjective
ra·tio·nal
ˈra-shə-nəl
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)
In re J. M., 642 A.2d 1062 (1994)
rationally
adverb
More from Merriam-Webster on rational
Nglish: Translation of rational for Spanish Speakers
Britannica English: Translation of rational for Arabic Speakers
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