UNFOUNDED Synonyms: 92 Similar and Opposite Words

unfounded

adjective

ˌən-ˈfau̇n-dəd

Definition of unfounded

as in unreasonable

having no basis in reason or fact the accusation proved to be unfounded

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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 Kelly said the initial report — a person with a rifle outside a church — is the kind of call that, in his experience, is usually unfounded. — Susan-Elizabeth Littlefield, CBS News, 28 Aug. 2026 In a way to perhaps poke fun at the unfounded rumors, Lil Yachty posted a photo of what appeared to be a behind-the-scene shot of Ice Spice wearing her fake baby bump. — Larisha Paul, Rolling Stone, 28 Aug. 2026 Local election officials had previously said the complaint was unfounded. — ABC News, 24 Aug. 2026 Still, that unfounded claim has continued to make some parents question the MMR shot, Handy said. — Annika Kim Constantino, CNBC, 21 Aug. 2026 See All Example Sentences for unfounded

Recent Examples of Synonyms for unfounded

Adjective

Your expectations of your stepsons aren’t unreasonable at all.

— R. Eric Thomas, Mercury News, 27 Aug. 2026
If the prosecution’s version of the evidence is reasonable and the defense’s is unreasonable, then that is not reasonable doubt.

— Christine Pelisek, PEOPLE, 25 Aug. 2026

Definition of unreasonable

Adjective

According to the popular—and scientifically baseless—myth, daddy longlegs spiders are among the most venomous spiders, but their fangs are too short to bite humans.

— Melissa Petruzzello, Encyclopedia Britannica, 2 Sep. 2026
Towers said that concerns about consent and explanation of risk are baseless.

— Amy Yurkanin, ProPublica, 24 Aug. 2026

Definition of baseless

Adjective

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
For Rocha, however, the claims examined in the documentary are groundless — and tiring.

— Johnny Dodd, PEOPLE, 15 July 2026

Definition of groundless

Adjective

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

Definition of unsubstantiated

Adjective

Last year, the panel also made several unwarranted changes to vaccine recommendations, including dropping the universal recommendation for a birth dose of the hepatitis B vaccine—a move widely decried by medical and health experts.

— Beth Mole, ArsTechnica, 24 Aug. 2026
At 79, Levy has been pleased to discover that often his discomfort is unwarranted.

— Matthew Jacobs, HollywoodReporter, 17 Aug. 2026

Definition of unwarranted

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unfortunately

unfounded

unfree

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

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Synonyms of unfounded

adjective

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