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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 Accurate voter lists and lawful mail-voting options are not unreasonable demands. — Lee Moak, New York Daily News, 18 Sep. 2026 The court ultimately upheld the search warrant, finding probable cause and concluded that obtaining the data remotely was not an unreasonable search. — Jihun Joun, The Conversation, 17 Sep. 2026 That’s not surprising or unreasonable, since those entities control college sports. — Michael McCann, Sportico.com, 16 Sep. 2026 While Tejeda noted that Taubman didn’t have any previous criminal history, Tejeda said the court found that Taubman posed an unreasonable risk to public safety. — Graham Womack, Sacbee.com, 15 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
  • Given the fact Iger did return to the company, that belief was not unwarranted.
    — Bethy Squires, Vulture, 24 Sep. 2026
  • Eritrean Information Minister Yemane Gebremeskel said the sanctions were unwarranted and caused considerable damage to his country.
    — ABC News, ABC News, 19 Sep. 2026
Definition of unwarranted
Adjective
  • Between restructuring waves, automation fears and flattening hierarchies, that concern isn’t always irrational.
    — Jonathan H. Westover, Forbes.com, 29 Sep. 2026
  • The fact, in other words, that there often isn’t a right answer or a clear victor—and that rational people are subject to irrational forces within and above them.
    — Max Norman, Harpers Magazine, 22 Sep. 2026
Definition of irrational
Adjective
  • Thankfully, my worries turned out to be unfounded, because the talent show in this episode turns out to be her time to shine.
    — Tom Smyth, Vulture, 28 Sep. 2026
  • An investigator later determined that Iv’s complaint against Plessy Cloud was unfounded, documents obtained by the Courant show.
    — Helen I. Bennett, Hartford Courant, 25 Sep. 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
  • Supporters of the three men said the allegations were baseless and contradicted by documentary evidence.
    — ABC News, ABC News, 23 Sep. 2026
  • The grand jury and Jackson County District Attorney Angel Myers McIlrath both concluded those allegations were baseless.
    — Adam Sabes, FOXNews.com, 22 Sep. 2026
Definition of baseless
Adjective
  • None of that is illegitimate, and none of it shows up on a data-residency dashboard.
    — Dr. Aditya Vikram Kashyap, Forbes.com, 22 Sep. 2026
  • The researchers suspect that others were created by AI that either hallucinated or, just like the AI agents browsing their file, couldn’t distinguish between legitimate and illegitimate instructions.
    — Dan Goodin, ArsTechnica, 27 Aug. 2026
Definition of illegitimate
Adjective
  • In 2018, a university climate survey revealed Native students felt the most unsupported on campus, according to Reed.
    — Emma Hall, Sacbee.com, 16 Sep. 2026
  • This reluctance is common and means many go unseen and unsupported, even when local organizations like Good Samaritan Outreach stand ready to help.
    — Christine Franz, The Orlando Sentinel, 8 Sep. 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

Browse Nearby Words

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 1 Oct. 2026.

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