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.
Unfounded claims that the Artemis II mission detected a mysterious moving object on the moon's surface also racked up millions of views across platforms.
From Barron's • Apr. 11, 2026
Unfounded claims about the Kinsey Institute’s work prompted the Indiana Legislature to block the flow of state dollars to the sex research institute.
From Los Angeles Times • May 23, 2023
Unfounded claims that the gunman was an immigrant living in the U.S. illegally, or transgender, quickly emerged on Twitter, Reddit and other social media platforms.
From Seattle Times • May 25, 2022
"There was no evidence presented which supports that Sofia received a physical or emotional injury. This case is closed as Unfounded."
From Fox News • Nov. 28, 2021
Unfounded rumors of an evil nature began to circulate during his lifetime, and naturally increased in virulence and volume after his death.
From The Philosophy of Spinoza by Ratner, Joseph
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.
