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.

Google filed a new challenge arguing before the bloc's top court, the European Court of Justice, that the case was unfounded and that the sanction penalised innovation.

From Barron's • Jul. 2, 2026

King: That there’s no one who’s going to have your journey, so try to just believe your own unfounded drive and see where it gets you.

From Los Angeles Times • Jun. 16, 2026

Now that he’s trying, he might find—though he will never publicly admit—that his critique was unfounded.

From Slate • Jun. 15, 2026

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

From The Wall Street Journal • May 20, 2026

Finding my apprehensions unfounded, however, and calmed by the deep silence that reigned as evening declined at nightfall, I took confidence.

From "Jane Eyre" by Charlotte Brontë

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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