unfounded

adjective

ˌən-ˈfau̇n-dəd How to pronounce unfounded (audio)
Definition of unfoundednext
as in unreasonable
having no basis in reason or fact the accusation proved to be unfounded

Synonyms & Similar Words

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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 unfounded In the lead-up to the 2022 vote, Jair Bolsonaro repeatedly cast unfounded doubts on Brazil's electronic voting system. — Arkansas Online, 4 Oct. 2026 Alito’s concerns are not unfounded, as threats to members in recent history have raised alarm about justices’ safety. — Claire Carter, The Washington Examiner, 4 Oct. 2026 To the broadcast crews, the fans were guilty until proven innocent, helping perpetuate the unfounded label that Fever fans were hateful, unruly and even discriminatory. — Jon Root Outkick, FOXNews.com, 3 Oct. 2026 In the lead-up to the 2022 vote, Jair Bolsonaro repeatedly cast unfounded doubts on Brazil’s electronic voting system. — Eléonore Hughes, Los Angeles Times, 3 Oct. 2026 See All Example Sentences for unfounded
Recent Examples of Synonyms for unfounded
  1. unreasonable
  2. baseless
  3. groundless
  4. unsubstantiated
  5. unwarranted
Adjective
  • Chad Marlow, a policy attorney with the ACLU, argues that citizens remain at risk for unreasonable surveillance under Missouri’s new guidelines.
    — Kendrick Calfee, Kansas City Star, 9 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
Definition of unreasonable
Adjective
  • 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
  • Supporters of the three men said the allegations were baseless and contradicted by documentary evidence.
    — ABC News, ABC News, 23 Sep. 2026
Definition of baseless
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
Adjective
  • Internal affairs complaints The lawsuit identifies five internal complaints filed against Sumstad between December 2022 and October 2025 and alleges each was dismissed, deemed unsubstantiated or ended in her exoneration.
    — Ben Wheeler, Kansas City Star, 24 Sep. 2026
  • Somehow this unsubstantiated story became internationally known with almost no major media explicitly reporting it, and before the modern version of the internet.
    — Allen Salkin, HollywoodReporter, 14 Sep. 2026
Definition of unsubstantiated
Adjective
  • 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
  • Given the fact Iger did return to the company, that belief was not unwarranted.
    — Bethy Squires, Vulture, 24 Sep. 2026
Definition of unwarranted

Browse Nearby Words

unfortunately
unfounded
unfree
See all Nearby Words

Cite this Entry

“Unfounded.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfounded. Accessed 14 Oct. 2026.

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