unsubstantiated

adjective

ˌən-səb-ˈstan(t)-shē-ˌā-təd How to pronounce unsubstantiated (audio)
Definition of unsubstantiatednext
as in unreasonable
having no basis in reason or fact an unsubstantiated claim that was thrown out of court

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 unsubstantiated While unsubstantiated claims and speculation circulate online about what led to the killings, Elikann emphasized the importance of following official facts over social media speculation. — Kelsie Cairns, FOXNews.com, 15 Aug. 2026 Those efforts were aided by Canary Mission and Betar, two pro-Israel groups that maintain online lists of Israel’s critics, often alongside unsubstantiated claims that they are affiliated with Hamas, according to the lawsuit. — Jake Offenhartz, Fortune, 15 July 2026 Conjecture over that evidence has fueled unsubstantiated conspiracy theories that there might have been a second shooter or that Kirk’s death was staged. — Hannah Schoenbaum, Chicago Tribune, 11 July 2026 Yoon, who faces other criminal cases as well, has promoted unsubstantiated election fraud claims circulated on YouTube to defend his botched power grab and rally conservative supporters against the Democrats. — ABC News, 7 July 2026 See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
  1. unreasonable
  2. unfounded
  3. baseless
  4. unsupported
Adjective
  • But Michael Edney, who worked at the OLC under Bush, said the opinion’s reading of executive privilege was not unreasonable, given the importance that some presidents place on outside consultation.
    — Perry Stein, Washington Post, 18 Oct. 2026
  • Both sides have accused each other of being unreasonable and of ignoring practical concerns about voting and election security, though in very different ways.
    — Kevin Rector, Los Angeles Times, 17 Oct. 2026
Definition of unreasonable
Adjective
  • The pullback isn't totally unfounded given the problems in its medical devices business.
    — Kevin Stankiewicz, CNBC, 13 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, ABC News, 12 Oct. 2026
Definition of unfounded
Adjective
  • Trump’s obsession with baseless election fraud claims and threats to rig or militarize our elections won’t help the recent college grad who’s sent out 300 resumes but can’t get a job.
    — S.E. Cupp, New York Daily News, 8 Oct. 2026
  • 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
Definition of baseless
Adjective
  • The update, spotted by MacRumors, also adds the iPad (6th generation) and BeatsX headphones to the unsupported list.
    — Jibin Joseph, PC Magazine, 15 Oct. 2026
  • This case involved a restaurant owner accused of underreporting more than US$2 million in business receipts and claiming unsupported depreciation deductions on rental properties.
    — Kaitlin Newkirk, The Conversation, 14 Oct. 2026
Definition of unsupported

Browse Nearby Words

unsubstantiality
unsubstantiated
unsubtle
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Cite this Entry

“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 20 Oct. 2026.

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