unfounded
Americanadjective
-
without foundation; not based on fact, realistic considerations, or the like.
unfounded suspicions.
- Synonyms:
- unjustified, false, idle, groundless, unsubstantiated
-
not established; not founded.
the prophet of a religion as yet unfounded.
adjective
-
(of ideas, allegations, etc) baseless; groundless
-
not yet founded or established
Other Word Forms
Etymology
Origin of unfounded
Explanation
Has someone ever told a complete lie about you? Then what they said was unfounded. There is nothing behind an unfounded statement. Things that are unfounded include lies, myths, and sometimes rumors. If something is unfounded, then there is no truth to it: the facts won't back it up. People often use this word when denying something: they'll say "Your words are unfounded!" Made-up creatures like unicorns and werewolves are unfounded. If you're writing a paper for school, you've better make sure nothing in your paper is unfounded — research the facts instead.
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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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.
The then deputy director, Jonathan Williams, wrote to Gradel five months later to say all the objects were accounted for and his claims were unfounded.
From BBC • Apr. 28, 2026
On the surface, that faith would appear entirely unfounded.
From BBC • Apr. 18, 2026
An organization-wide test in the minors proved those concerns were unfounded.
From The Wall Street Journal • Apr. 15, 2026
The warrants have yet to be released, but they are expected to provide the first glimpse into the contested court documents related to the allegations of fraud — claims that officials say are unfounded.
From Los Angeles Times • Apr. 8, 2026
Now she’d see that her fears were unfounded.
From "In the Time of the Butterflies" by Julia Alvarez
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.