unfounded

adjective

un·​found·​ed ˌən-ˈfau̇n-dəd How to pronounce unfounded (audio)
Synonyms of unfoundednext
: lacking a sound basis : groundless, unwarranted
an unfounded accusation

Synonyms of unfounded

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Examples of unfounded in a Sentence

the accusation proved to be unfounded
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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.
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 But Shanske says arguments that the proposal would prove administratively unworkable are unfounded. — Trevor Laurence Jockims, CNBC, 22 Oct. 2026 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 See All Example Sentences for unfounded

Word History

First Known Use

1648, in the meaning defined above

Time Traveler
The first known use of unfounded was in 1648

Rhymes for unfounded

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unfounded
unfoundedly
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Cite this Entry

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

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Kids Definition

unfounded

adjective
un·​found·​ed ˌən-ˈfau̇n-dəd How to pronounce unfounded (audio)
ˈən-
: lacking a sound base : groundless
unfounded suspicions
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