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 The trend has been fueled in part by unfounded claims that jets are spraying chemicals to control people’s minds or manipulate the weather. — Elizabeth Robinson, NBC news, 19 Aug. 2026 From the energizing first news conference upon his return to the way the coaching staff and players reacted to both his Kansas City comeback and the tragic implications of his recent time away, those apprehensions seem unfounded. — Kansas City Star, 18 Aug. 2026 An initial report that the incident involved a vehicle collision was later determined to be unfounded, according to the Sheriff’s Office. — Sacbee.com, 17 Aug. 2026 Nonetheless, emphasizing unfounded truths in various frantic phrases won’t gain followers to your point of view. — Sun Sentinel Editorial Board, Sun Sentinel, 15 Aug. 2026 See All Example Sentences for unfounded

Recent Examples of Synonyms for unfounded

Adjective

The parties have blamed each other for trying to make unreasonable last-minute changes to their agreement.

— Kevin Breuninger,Michael Wayland, CNBC, 24 Aug. 2026
The investigation found Brazilian policies unreasonable or discriminatory toward US commerce.

— Joshua Hong, Fortune, 21 Aug. 2026

Definition of unreasonable

Adjective

Towers said that concerns about consent and explanation of risk are baseless.

— Amy Yurkanin, ProPublica, 24 Aug. 2026
And Democratic aides in Washington are preparing members of Congress to push back in the court of public opinion against any baseless claims of voter fraud in competitive districts.

— Kevin Rector, Los Angeles Times, 23 Aug. 2026

Definition of baseless

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 1 Sep. 2026.

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Synonyms of unfounded

adjective

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