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 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 Its inclusion in the documentary has provided ammunition for Musk supporters and his lawyers to discredit the film, pointing to an unfounded conspiracy theory about SpaceX’s Starlink satellites interfering in the election. — ABC News, 12 Oct. 2026 Supporters of the rule change also spoke against the COVID vaccine and the measles, mumps and rubella vaccine (MMR), repeating unfounded claims, such as that doctors make money from vaccines and that vaccines cause autism. — Ana Goñi-Lessan, Sun Sentinel, 8 Oct. 2026 These online rumors are hardly new—unfounded claims of European bans on wheeled luggage have been circulating for more than 10 years. — Amelia McBride, Travel + Leisure, 8 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
  • With 20th Television increasingly focused on supplying Disney platforms, integrating the two areas would not be unreasonable.
    — Nellie Andreeva, Deadline, 5 Nov. 2026
  • Frimpong concluded that plaintiffs were likely to prove the practice violated the 4th Amendment’s protection against unreasonable seizures and the 5th Amendment’s guarantee of equal protection.
    — Brittny Mejia, Los Angeles Times, 29 Oct. 2026
Definition of unreasonable
Adjective
  • Ethiopia’s Foreign Ministry rejected similar Sudanese accusations in a May 5 statement, calling them baseless, and accused Sudan of supporting rebels in its northern Tigray region.
    — ABC News, ABC News, 4 Nov. 2026
  • The Central Elections Committee officially dismissed claims of widespread fraud as baseless and said there is no evidentiary basis for alleging a systematic compromise of the vote.
    — Tal Shalev, CNN Money, 2 Nov. 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
  • Blades Brown was in the field in Mexico and finished a respectable T-19, and during the event, an unsubstantiated yet absolutely hysterical rumor about the teenage phenom made the rounds in the golf world.
    — Mark Harris OutKick, FOXNews.com, 2 Nov. 2026
  • Netanyahu’s unsubstantiated claims of election interference have drawn swift rebukes, as the opposition considers using its numbers to shape the Knesset before a new government is formed.
    — Cara Anna, Los Angeles Times, 30 Oct. 2026
Definition of unsubstantiated
Adjective
  • His disparaging comments bemoaning the lack of financial support of UConn football by the state, UConn and Pratt & Whitney were totally unwarranted.
    — Letters to the Editor, Hartford Courant, 29 Oct. 2026
  • Ashlee Jordan, a 29-year-old Bridgewater woman who was a former Title Clerk at the Quincy RMV, was charged with one count of bribery, one count of unwarranted privilege, and one count of conspiracy to commit title fraud.
    — Matt Schooley, CBS News, 28 Oct. 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 11 Nov. 2026.

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