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 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 Only 9 percent were substantiated; 52 percent were found either to be unfounded or to involve conduct within NYPD guidelines. — Daniel Edward Rosen, Washington Post, 8 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 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 See All Example Sentences for unfounded
Recent Examples of Synonyms for unfounded
  1. unreasonable
  2. baseless
  3. groundless
  4. unsubstantiated
  5. unwarranted
Adjective
  • That triggers First Amendment protection, and that means there cannot be viewpoint discrimination or unreasonable restrictions that are inconsistent with the speech activities imposed on the journalists.
    — Ted Johnson, Deadline, 30 Oct. 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
  • State officials denounced the letters as a legally baseless intimidation tactic.
    — Kevin Rector, Los Angeles Times, 28 Oct. 2026
  • Trump unleashed a series of personal and baseless attacks against Hamilton at the rally in Park City, Kansas -- about 10 miles north of Wichita -- with just two weeks out from election day as the balance of power in the Senate hangs in the balance.
    — ABC News, ABC News, 20 Oct. 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
  • Bolsonaro has refused to concede defeat and has made unsubstantiated accusations of election fraud.
    — MATTHEW LEE, Arkansas Online, 28 Oct. 2026
  • While unsubstantiated rumors of Dykes’ ousting were flying, Baylor fired football coach Dave Aranda.
    — Mac Engel October 28, Fort Worth Star-Telegram, 28 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
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Cite this Entry

“Unfounded.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unfounded. Accessed 4 Nov. 2026.

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