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 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 Some Democrats fear Trump could use those unsubstantiated assertions as a pretext to intervene in November. — Susan Page, USA Today, 1 Sep. 2026 Many are leaning into their own unsubstantiated suppositions, even those not backed by evidence. — Rebekah Riess, CNN Money, 22 Aug. 2026 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 See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
  1. unreasonable
  2. unfounded
  3. baseless
  4. unsupported
Adjective
  • On the surface, paying as low as 24 cents for an hour of streaming game time doesn’t sound completely unreasonable.
    — Kyle Orland, ArsTechnica, 21 Oct. 2026
  • If Putin rejects the framework — or, more likely, demands unreasonable changes — then the world will at least know who blocked the fledgling peace effort.
    — David Ignatius, Washington Post, 21 Oct. 2026
Definition of unreasonable
Adjective
  • The investigation was closed after authorities determined Thompson’s claims were unfounded, the department said.
    — Elizabeth Campbell, Fort Worth Star-Telegram, 23 Oct. 2026
  • Stewart, a potent running quarterback for the Pittsburgh Steelers, was the talk of the industry when an unfounded rumor about him being gay threatened to derail everything.
    — K. Thor Jensen, PC Magazine, 23 Oct. 2026
Definition of unfounded
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
  • Nvidia has gone to great lengths to secure support from game publishers, but many titles remain unsupported at the time of writing.
    — Joe Osborne, PC Magazine, 17 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
See all Nearby Words

Cite this Entry

“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 29 Oct. 2026.

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