unreasonable

adjective

ˌən-ˈrēz-nə-bəl
Definition of unreasonablenext
1
as in unwarranted
having no basis in reason or fact an unreasonable assumption

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
as in irrational
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 Brady pointed to a legal doctrine known as laches, which can prevent a party from pursuing a claim after an unreasonable delay that prejudices another party. — Gino Vicci, CBS News, 12 Oct. 2026 The factors most closely tied to burnout included unfair treatment, crushing workloads, unclear expectations, poor communication and support from managers, and unreasonable deadlines. — Christos Makridis, The Conversation, 7 Oct. 2026 But several individually reasonable events, viewed together and over time, can tell an unreasonable story. — Shahen Minasyan, Forbes.com, 24 Sep. 2026 At the outset of the Biden administration in January 2021, NASA was still targeting a 2024 lunar landing, even though this was widely seen as unreasonable. — Eric Berger, ArsTechnica, 23 Sep. 2026 See All Example Sentences for unreasonable
Recent Examples of Synonyms for unreasonable
  1. unwarranted
  2. irrational
  3. unfounded
  4. unreasoning
  5. baseless
  6. illegitimate
  7. unsupported
  8. groundless
Adjective
  • While we are relieved that Heidi has received medical care and is safe, we are outraged by this unwarranted attack on a journalist doing her job and urge a thorough investigation and follow-through from authorities.
    — Arkansas Online, Arkansas Online, 17 Oct. 2026
  • Critics have argued that much of the data collected is from people who are not suspected of any wrongdoing, amounting to unwarranted surveillance of lawful activities.
    — Carlos E. Castañeda, CBS News, 29 Sep. 2026
Definition of unwarranted
Adjective
  • The industrial revolutions of the past produced enormous value alongside bankruptcies, dislocations, and periods of irrational exuberance.
    — Brian Solis, Forbes.com, 5 Oct. 2026
  • If anyone can reconstruct Apéry’s reasoning, the odd values of zeta may finally be proven irrational.
    — Lyndie Chiou, Scientific American, 2 Oct. 2026
Definition of irrational
Adjective
  • The Republican accused Bradley of lying about the circumstances of her absence, an allegation Bradley’s campaign said was unfounded.
    — Mary Ramsey, Charlotte Observer, 16 Oct. 2026
  • The pullback isn't totally unfounded given the problems in its medical devices business.
    — Kevin Stankiewicz, CNBC, 13 Oct. 2026
Definition of unfounded
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
  • Trump’s obsession with baseless election fraud claims and threats to rig or militarize our elections won’t help the recent college grad who’s sent out 300 resumes but can’t get a job.
    — S.E. Cupp, New York Daily News, 8 Oct. 2026
  • Homeland Security Secretary Markwayne Mullin publicly claimed in July — without providing evidence — that there may be more than 190,000 such voters on California rolls, a claim California officials dismissed as baseless.
    — Kevin Rector, Los Angeles Times, 29 Sep. 2026
Definition of baseless
Adjective
  • An adult child can claim authority over the meaning of a life without proving that everything inherited is therefore illegitimate.
    — Literary Hub, Literary Hub, 9 Oct. 2026
  • Saman admitted to purchasing much of his inventory from brokers or middlemen, which the department identified as illegitimate distributors of the brands.
    — Glenn Taylor, Footwear News, 8 Oct. 2026
Definition of illegitimate
Adjective
  • The update, spotted by MacRumors, also adds the iPad (6th generation) and BeatsX headphones to the unsupported list.
    — Jibin Joseph, PC Magazine, 15 Oct. 2026
  • This case involved a restaurant owner accused of underreporting more than US$2 million in business receipts and claiming unsupported depreciation deductions on rental properties.
    — Kaitlin Newkirk, The Conversation, 14 Oct. 2026
Definition of unsupported
Adjective
  • Ye Khaung Kyaw and the two other men charged in connection with the case have said the accusations against them are groundless.
    — Arkansas Online, Arkansas Online, 24 Sep. 2026
  • Social media in South Korea have been filled with messages stoking fears about safety on Jeju, with some spreading groundless rumors and deriding the island.
    — Hyung-Jin Kim, Los Angeles Times, 27 Aug. 2026
Definition of groundless

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unreason
unreasonable
unreasonableness
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Cite this Entry

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

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