unsubstantiated

adjective

un·​sub·​stan·​ti·​at·​ed ˌən-səb-ˈstan(t)-shē-ˌā-təd How to pronounce unsubstantiated (audio)
Synonyms of unsubstantiatednext
: not proven to be true : not substantiated
an unsubstantiated rumor/report
a plausible but unsubstantiated theory

Synonyms of unsubstantiated

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Examples of unsubstantiated in a Sentence

an unsubstantiated claim that was thrown out of court
Recent Examples on the Web
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.
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 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 Bolsonaro has refused to concede defeat and has made unsubstantiated allegations of election fraud. — CBS News, 27 Oct. 2026 See All Example Sentences for unsubstantiated

Word History

First Known Use

circa 1775, in the meaning defined above

Time Traveler
The first known use of unsubstantiated was circa 1775

Rhymes for unsubstantiated

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Browse Nearby Words

unsubstantiate
unsubstantiated
unsubstituted
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Cite this Entry

“Unsubstantiated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsubstantiated. Accessed 1 Nov. 2026.

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