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Definitions

well-founded

[wel-foun-did] / ˈwɛlˈfaʊn dɪd /
ADJECTIVE
based on sound reasoning
Synonyms
WEAK
based on hard data based on hard facts factual proven rock solid solid substantiated

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

The big test comes Tuesday, when UnitedHealth reports third-quarter results and investors see whether Warren Buffett’s enthusiasm for the stock was well-founded.

From Barron's • Oct. 27, 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