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Showing results for unfounded. Search instead for un-founded.
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.

But instead of quelling the speculation, the video fueled a new wave of unfounded theories.

From Barron's • Apr. 2, 2026

Levy: I have a completely unfounded fear of being trapped in an organized criminal situation.

From Los Angeles Times • Apr. 1, 2026

Having overturned a 2-0 deficit to stun Manchester City at the same stage last season, that confidence is not unfounded.

From BBC • Apr. 1, 2026

"By shedding light on the biology and ecology of the great white shark, research can help replace unfounded myths with genuine understanding."

From Science Daily • Mar. 11, 2026

The only way he could roll it off would be to learn that his fears were unfounded.

From "The House of the Scorpion" by Nancy Farmer

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.