unfounded

adjective

un·​found·​ed ˌən-ˈfau̇n-dəd How to pronounce unfounded (audio)
Synonyms of unfoundednext
: lacking a sound basis : groundless, unwarranted
an unfounded accusation

Synonyms of unfounded

Relevance
See All Synonyms & Antonyms in Thesaurus

Examples of unfounded in a Sentence

the accusation proved to be unfounded
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The Republican accused Bradley of lying about the circumstances of her absence, an allegation Bradley’s campaign said was unfounded. — Mary Ramsey, Charlotte Observer, 16 Oct. 2026 The pullback isn't totally unfounded given the problems in its medical devices business. — Kevin Stankiewicz, CNBC, 13 Oct. 2026 Its inclusion in the documentary has provided ammunition for Musk supporters and his lawyers to discredit the film, pointing to an unfounded conspiracy theory about SpaceX’s Starlink satellites interfering in the election. — ABC News, 12 Oct. 2026 Only 9 percent were substantiated; 52 percent were found either to be unfounded or to involve conduct within NYPD guidelines. — Daniel Edward Rosen, Washington Post, 8 Oct. 2026 See All Example Sentences for unfounded

Word History

First Known Use

1648, in the meaning defined above

Time Traveler
The first known use of unfounded was in 1648

Rhymes for unfounded

See All Rhymes for unfounded

Browse Nearby Words

unfound
unfounded
unfoundedly
See all Nearby Words

Cite this Entry

“Unfounded.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unfounded. Accessed 27 Oct. 2026.

Copy Citation

Kids Definition

unfounded

adjective
un·​found·​ed ˌən-ˈfau̇n-dəd How to pronounce unfounded (audio)
ˈən-
: lacking a sound base : groundless
unfounded suspicions
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Last Updated: - Updated example sentences

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of milieu

See Definitions and Examples »

Popular in Grammar & Usage

See More

How to Use 'Who' vs. 'Whom'

Merriam-Webster’s Great Big List of Words You Love to Hate

'Affect' vs. 'Effect'

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?
See More

Popular in Wordplay

See More

The Longest Long Words List

9 Words That Sound Like Insults But Aren't

12 Lovely and Unusual Words for the Natural World

Why do we 'bury the lede?'

'Za' and 9 Other Words to Help You Win at SCRABBLE
See More

Popular

See More

How to Use 'Who' vs. 'Whom'

The Longest Long Words List

9 Words That Sound Like Insults But Aren't
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
different halloween monsters in silhouette
A Monstrous Vocab Quiz Words That Go Bump in the Night
See All