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Synonyms

unfounded

American  
[uhn-foun-did] / ʌnˈfaʊn dɪd /

adjective

  1. without foundation; not based on fact, realistic considerations, or the like.

    unfounded suspicions.

    Synonyms:
    unjustified, false, idle, groundless, unsubstantiated
  2. not established; not founded.

    the prophet of a religion as yet unfounded.


unfounded British  
/ ʌnˈfaʊndɪd /

adjective

  1. (of ideas, allegations, etc) baseless; groundless

  2. not yet founded or established

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of unfounded

First recorded in 1640–50; un- 1 + found 1 + -ed 2

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.

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Vocabulary lists containing unfounded

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.

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

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

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

He was soon wading oftener than he was walking, but the thick, soft mud felt good to his feet, and he wandered aimlessly on, trying to make himself believe that his suspicions were unfounded.

From "The Golden Goblet" by Eloise Jarvis McGraw

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