Definitions

unfounded

[uhn-foun-did] / ʌnˈfaʊn dɪd /

ADJECTIVE

not based on fact

Synonyms

STRONGEST

baseless deceptive fabricated false gratuitous groundless illogical misleading spurious unjustified unproven unsubstantiated untrue untruthful unwarranted

WEAK

fallacious foundationless idle mendacious off-base trumped-up uncalled-for unreal vain without basis without foundation

Antonyms

STRONGEST

called-for correct genuine honest justified real reasonable right true truthful warranted

WEAK

founded proven substantiated supported

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Jonathan’s legal team say he is innocent and that the homicide allegation is unfounded.

From The Wall Street Journal • May 20, 2026

Yes, your daughter paid the mortgage the rest of the time — not a small feat given the wider context — but it also demonstrates that your concerns are not entirely unfounded.

From MarketWatch • May 12, 2026

An organization-wide test in the minors proved those concerns were unfounded.

From The Wall Street Journal • Apr. 15, 2026

Maybe they do blame themselves, and are paralyzed by an unfounded shame.

From Los Angeles Times • Apr. 14, 2026

I knew that some people blamed G. R. Naidoo, my Durban host, a suggestion I believe was unfounded.

From "Long Walk to Freedom" by Nelson Mandela

Vocabulary lists containing unfounded

Fake It 'Til You Make It: Synonyms for "False"

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100 SAT Words Beginning with "U"

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"Laws are not the only way to boost immunization”: an editorial from Nature

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