UNREASONABLE Synonyms: 124 Similar and Opposite Words

unreasonable

adjective

ˌən-ˈrēz-nə-bəl

Definition of unreasonable

as in irrational

having no basis in reason or fact an unreasonable assumption

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in unreasoning

not using or following good reasoning an unreasonable respect for a man who did not deserve it

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of unreasonable In such an environment, Fundstrat’s Tom Lee has argued that the S & P 500 can climb to 8,000 over the next few weeks, a level that is not too unreasonable given that the broader index was last trading around 7,750 — only 3% away. — Sarah Min, CNBC, 7 Aug. 2026 Which is not entirely unreasonable given this very specific set of circumstances. — Brian Grubb, Vulture, 3 Aug. 2026 Recalls are issued when vehicle owners, regulators, or manufacturers determine that a potentially faulty component presents an unreasonable safety risk or fails to meet specified standards. — Jim Gorzelany, Forbes.com, 31 July 2026 There are many algorithms for which it has been mathematically proven that a quantum computer can generate results that would take a classical computer an unreasonable amount of time to generate. — ArsTechnica, 30 July 2026 See All Example Sentences for unreasonable

Recent Examples of Synonyms for unreasonable

Adjective

But the question remained unsolved for polygons with irrational angles.

— Sam Macdonald, Scientific American, 14 Aug. 2026
As a result, the argument goes, today's spending is irrational because the hardware would need to be replaced too frequently to generate an attractive return on investment, known as ROI.

— , CNBC, 12 Aug. 2026

Definition of irrational

Adjective

But in each event—in the living act, the undoubted deed—there, some unknown but still reasoning thing puts forth the mouldings of its features from behind the unreasoning mask.

— Literary Hub, Literary Hub, 6 July 2026
Roosevelt surely understood that nameless, unreasoning, unjustified fear cannot be eradicated.

— New York Times, New York Times, 9 June 2026

Definition of unreasoning

Adjective

Federal judges have quashed many of the subpoenas as illegitimate efforts to intimidate providers into ending care.

— ABC News, ABC News, 14 Aug. 2026
But that’s forcing them to wrestle with the idea that any action taken by a party is illegitimate, anti-democratic rigging — something the other team can use to depress the base.

— David Weigel, semafor.com, 22 July 2026

Definition of illegitimate

Adjective

The investigating officers in the 2012 Delray Beach incident determined the allegations against Caruso to be unfounded, according to police records, after the child did not tell them about any untoward incident in interviews.

— Claire Heddles, Miami Herald, 20 Aug. 2026
Based on the data, 71% of the 485 grievances were deemed as unfounded or rejected by detention center officials.

— Vanessa Romo, NPR, 20 Aug. 2026

Definition of unfounded

Adjective

How sad that aiding much healthier and happier living comes with baseless lawsuits.

— John Tamny, Forbes.com, 18 Aug. 2026
Judge Lebovits ruled in favor with the Times according to New York State’s Anti-SLAPP law, which protects against baseless legal proceedings stemming from attempts to stifle the press or free speech.

— Fran Hoepfner, Vulture, 28 July 2026

Definition of baseless

Adjective

Paul argued Fauci using the Fifth Amendment was unsupported because former President Joe Biden, whom Fauci advised during the pandemic, pardoned him.

— Scott Thompson, FOXNews.com, 3 Aug. 2026
Sherrill rejected that request Tuesday, calling it unsupported by law.

— Kaelan Deese, The Washington Examiner, 30 July 2026

Definition of unsupported

Adjective

Specifically, Edgerton is asking the court to declare the petition void, rule that its data center prohibition is an invalid and permanently prevent the ordinance from being submitted to voters.

— Kendrick Calfee, Kansas City Star, 15 Aug. 2026
The government maintains that the request for class certification came too late and is invalid anyway.

— Kevin Breuninger, CNBC, 5 Aug. 2026

Definition of invalid

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unreason

unreasonable

unreasonableness

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“Unreasonable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unreasonable. Accessed 22 Aug. 2026.

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Synonyms of unreasonable

adjective

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