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 Your expectations of your stepsons aren’t unreasonable at all. — R. Eric Thomas, Mercury News, 27 Aug. 2026 If the prosecution’s version of the evidence is reasonable and the defense’s is unreasonable, then that is not reasonable doubt. — Christine Pelisek, PEOPLE, 25 Aug. 2026 The investigation found Brazilian policies unreasonable or discriminatory toward US commerce. — Joshua Hong, Fortune, 21 Aug. 2026 The surrogate must have previously given birth to at least one child, and a doctor must determine that another pregnancy wouldn’t pose an unreasonable risk to her or the baby. — Tiffani Jackson, Fort Worth Star-Telegram, 19 Aug. 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
  • Last year, the panel also made several unwarranted changes to vaccine recommendations, including dropping the universal recommendation for a birth dose of the hepatitis B vaccine—a move widely decried by medical and health experts.
    — Beth Mole, ArsTechnica, 24 Aug. 2026
  • At 79, Levy has been pleased to discover that often his discomfort is unwarranted.
    — Matthew Jacobs, HollywoodReporter, 17 Aug. 2026
Definition of unwarranted
Adjective
  • So the strongest performers tend to resist hardest, and their response is not irrational.
    — Pankaj Prasoon, Forbes.com, 2 Sep. 2026
  • But the question remained unsolved for polygons with irrational angles.
    — Sam Macdonald, Scientific American, 14 Aug. 2026
Definition of irrational
Adjective
  • Yet her decision to spread unfounded theories of conspiracy fraud helped to land Fox in court.
    — David Folkenflik, NPR, 3 Sep. 2026
  • Garza wrote in her complaint that the accusations were unfounded and claimed that LeVota refused to show her the email.
    — Ben Wheeler, Kansas City Star, 2 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
  • According to the popular—and scientifically baseless—myth, daddy longlegs spiders are among the most venomous spiders, but their fangs are too short to bite humans.
    — Melissa Petruzzello, Encyclopedia Britannica, 2 Sep. 2026
  • Towers said that concerns about consent and explanation of risk are baseless.
    — Amy Yurkanin, ProPublica, 24 Aug. 2026
Definition of baseless
Adjective
  • 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
  • Internet discussions portrayed the SPLC as a politically motivated or illegitimate actor.
    — Art Jipson, The Conversation, 20 Aug. 2026
Definition of illegitimate
Adjective
  • Educational technology products built on generative AI often make unsupported claims of improving young students' learning and critical thinking skills, according to an APA report co-authored by Barnes that published on Thursday.
    — Tom Huddleston Jr., CNBC, 5 Sep. 2026
  • Such accusations, while unsupported, undoubtedly place Magnus, a top Disney executive, in an uncomfortable position.
    — Bobby Burack OutKick, FOXNews.com, 4 Sep. 2026
Definition of unsupported
Adjective
  • 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
  • For Rocha, however, the claims examined in the documentary are groundless — and tiring.
    — Johnny Dodd, PEOPLE, 15 July 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 9 Sep. 2026.

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