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
When LLMs were given the freedom to determine their own target amounts and betting sizes, bankruptcy rates rose substantially alongside instances of irrational behavior, demonstrating that greater autonomy amplifies risk-taking tendencies.
—
Rosa Lyster, Harpers Magazine, 30 Dec. 2025
In a court of law, though, irrational reactions—such as a sustained relationship with an abuser—can fatally undermine a victim’s credibility.
—Sophie Gilbert, The Atlantic, 22 Dec. 2025
To prevent yourself from imposing irrational penalties, set up house rules that outline logical consequences in advance.
—Leslie Garisto Pfaff, Parents, 20 Dec. 2025
For instance, mathematicians know that most numbers are irrational, meaning that they can’t be written as a fraction of two whole numbers.
—Jordana Cepelewicz, Quanta Magazine, 18 Dec. 2025
See All Example Sentences for irrational
Rosa Lyster, Harpers Magazine, 30 Dec. 2025
In a court of law, though, irrational reactions—such as a sustained relationship with an abuser—can fatally undermine a victim’s credibility.
—Sophie Gilbert, The Atlantic, 22 Dec. 2025
To prevent yourself from imposing irrational penalties, set up house rules that outline logical consequences in advance.
—Leslie Garisto Pfaff, Parents, 20 Dec. 2025
For instance, mathematicians know that most numbers are irrational, meaning that they can’t be written as a fraction of two whole numbers.
—Jordana Cepelewicz, Quanta Magazine, 18 Dec. 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 11 Jan. 2026.
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