as in unreasonable
not using or following good reasoning
it's irrational to think that you can continue to consume an excess of calories and not gain weight
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Recent Examples of irrational
The study, published on the research platform arXiv, found that once the models were allowed to vary their bets and set their own targets, irrational behavior surged — and bankruptcy became a common outcome.
—
Jesus Mesa, MSNBC Newsweek, 22 Oct. 2025
Poetry brings hope, not an irrational optimism or wishful thinking, but a positive orientation to the future, of what a better, healthier future would look like.
—K.j.s. “sunny” Anand, Time, 15 Oct. 2025
Marks believes that investor optimism doesn’t automatically signal irrational exuberance.
—Yun Li, CNBC, 13 Oct. 2025
That irrational choice, born of struggle and longing, changed my life.
—Sudhir Gupta, Rolling Stone, 7 Oct. 2025
See All Example Sentences for irrational
Jesus Mesa, MSNBC Newsweek, 22 Oct. 2025
Poetry brings hope, not an irrational optimism or wishful thinking, but a positive orientation to the future, of what a better, healthier future would look like.
—K.j.s. “sunny” Anand, Time, 15 Oct. 2025
Marks believes that investor optimism doesn’t automatically signal irrational exuberance.
—Yun Li, CNBC, 13 Oct. 2025
That irrational choice, born of struggle and longing, changed my life.
—Sudhir Gupta, Rolling Stone, 7 Oct. 2025
See All Example Sentences for irrational
Recent Examples of Synonyms for irrational
Adjective
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Importantly, the president already has full legal authority to impose tariffs when other nations’ behavior places an unreasonable burden on our economy, including through environmental negligence.—
Chip Lamarca,
Sun Sentinel,
6 Jan. 2026
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The logic was that Spirit had projected the league would grow at a rate that the league itself found unreasonable, and so would not be able to field a team while also paying Rodman.—
Louisa Thomas,
New Yorker,
4 Jan. 2026
Adjective
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Let sound political prescience but take the place of an unreasoning prejudice, and this will be done.—
Frederick Douglass,
The Atlantic,
16 Aug. 2017
Adjective
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Trump took decisive action Saturday in launching precision military strikes in Venezuela that enabled special forces to seize and detain Maduro, an illegitimate leader despised by his own people.—
Lauren Green,
The Washington Examiner,
5 Jan. 2026
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Rubio insisted in interviews that Washington will use control of Venezuela’s oil industry to force policy changes, and called the government currently in place illegitimate.—
Regina Garcia Cano,
Fortune,
4 Jan. 2026
Cite this Entry
“Irrational.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/irrational. Accessed 9 Jan. 2026.
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