Synonyms

well-founded

American

[wel-foun-did] / ˈwɛlˈfaʊn dɪd /

adjective

having a foundation in fact; based on good reasons, information, etc..

well-founded suspicions.

well-founded British

adjective

having good grounds

well-founded rumours

"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

Etymology

Origin of well-founded

Middle English word dating back to 1325–75

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 most current estimates of future inflation fall within a narrow range, giving us at least some confidence that the real yields based on those estimates are well-founded.

From MarketWatch • Apr. 8, 2026

But when accommodation expands without clear boundaries or meaningful verification, its credibility erodes and skepticism grows about even well-founded uses.

From The Wall Street Journal • Feb. 19, 2026

Thousands of mourners turned out for his funeral in Moscow in March 2024 despite well-founded fears of a police crackdown.

From BBC • Sep. 17, 2025

And those concerns turned out to be all too well-founded.

From Salon • Aug. 31, 2025

All things here were well-founded, peaceful, and assured; and Ged looking about him at the firelit room said, “This is how a man should live,” and sighed.

From "A Wizard of Earthsea" by Ursula K. Le Guin

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023