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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Example Sentences
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Recent Examples of irrational
Economist Hyman Minsky spent his career explaining how irrational behavior produces fragility and instability in capitalist systems.
—
Hersh Shefrin,
Forbes.com,
23 June 2026
McClanahan has been close enough to his usual production, but without an irrational need for perfection.
—
Tyler Kepner,
New York Times,
21 June 2026
Lagrange Numbers as a Measure of Irrationality At the end of the 19th century mathematician Andrey Markov took another pass at this challenge by omitting the golden ratio and focusing on the remaining irrational values.
—
Manon Bischoff,
Scientific American,
19 June 2026
Bill stutters an affirmative response that captures every man who has held out irrational hope that a woman will return to him.
—
Stephen Rodrick,
Rolling Stone,
16 June 2026
See All Example Sentences for irrational
Hersh Shefrin,
Forbes.com,
23 June 2026
McClanahan has been close enough to his usual production, but without an irrational need for perfection.
—
Tyler Kepner,
New York Times,
21 June 2026
Lagrange Numbers as a Measure of Irrationality At the end of the 19th century mathematician Andrey Markov took another pass at this challenge by omitting the golden ratio and focusing on the remaining irrational values.
—
Manon Bischoff,
Scientific American,
19 June 2026
Bill stutters an affirmative response that captures every man who has held out irrational hope that a woman will return to him.
—
Stephen Rodrick,
Rolling Stone,
16 June 2026
See All Example Sentences for irrational
Recent Examples of Synonyms for irrational
Adjective
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If these requirements are not met, the search is unreasonable and therefore unlawful, and evidence obtained in that search cannot be used in court, barring a good-faith exception.
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Justices ruled that sweeping use of cellphone data requires a warrant, a decision applying the Fourth Amendment, which protects against unreasonable searches and seizures, to new technology.
Adjective
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Roosevelt surely understood that nameless, unreasoning, unjustified fear cannot be eradicated.
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Bainbridge knew about secrets and unreasoning shame.
Adjective
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That difference suggests that the government sees this extension of patent rights as an illegitimate way for a company to exclude other companies from competing.
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Some fraudsters run an illegitimate DME company and get a doctor to prescribe the equipment.
Cite this Entry
“Irrational.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/irrational. Accessed 3 Jul. 2026.
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