WELL-FOUNDED Synonyms: 112 Similar and Opposite Words

well-founded

adjective

ˈwel-ˈfau̇n-dəd

Definition of well-founded

as in logical

according to the rules of logic even a well-founded argument can lead to an erroneous conclusion if one of the premises is incorrect

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in reasonable

based on sound reasoning or information a well-founded complaint about the business's treatment of its customers

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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.

Recent Examples of well-founded Gen Z’s concerns are well-founded—and echo warnings from leading AI experts and mounting management evidence. — Steve Denning, Forbes.com, 14 June 2026 Advertisement Barring Platner bowing out in time—which seems unlikely—Democrats are hunkering down, desperately hoping there aren’t more Platner revelations left to come out before Election Day. — Philip Elliott, Time, 10 June 2026 The opponents’ concerns are well-founded. — Alex Weatherall, Boston Herald, 10 June 2026 Add to that an affordability crisis hitting families’ checkbooks and many businesses’ eager push to utilize artificial intelligence, and workers’ sentiments appear well-founded. — Matt Helmer, Fortune, 23 May 2026 See All Example Sentences for well-founded

Recent Examples of Synonyms for well-founded

Adjective

That work, first demonstrated at 12 logical qubits, extends directly into today’s result, as per the release.

— Prabhat Ranjan Mishra, Interesting Engineering, 25 Sep. 2026
As of July 2026, the current record is just under 100 logical qubits.

— Manon Bischoff, Scientific American, 22 Sep. 2026

Definition of logical

Adjective

No reasonable person looking at her case would have called her a threat to anyone.

— Don Bacon, Washington Post, 25 Sep. 2026
Defense lawyer Dameka Davis told the jury prosecutors failed at the first task of a murder trial — to prove beyond a reasonable doubt that the victim was dead.

— Rafael Olmeda, Sun Sentinel, 24 Sep. 2026

Definition of reasonable

Adjective

Payday loans Usually capped at $500, payday loans are a form of short-term financing that typically only require a valid ID, proof of income and an active checking account.

— Dan Avery, CNBC, 25 Sep. 2026
All forms of grief are valid, and the beautiful thing about this story is that in the end there was finally a reunification between the two sides.

— Roberto Prieto, Variety, 25 Sep. 2026

Definition of valid

Adjective

In layman’s terms, critical thinking is the ability to think independently by questioning claims, weighing evidence, and making reasoned judgments.

— Ted Ladd, Forbes.com, 29 Aug. 2026
None are credible challengers; Matt Conroy is the more reasoned and moderate of the three.

— The Editorial Board, Chicago Tribune, 11 Feb. 2026

Definition of reasoned

Adjective

Founded by two British academics almost two decades ago, Effective Altruism is a philosophical movement whose core idea is that people should try to use rational processes to do the most good for the most people in the world.

— Beatrice Nolan, Fortune, 23 Sep. 2026
This is not to impugn the nobility of counting, of the close and careful observation of nature, of the rational, ordered efforts to understand it.

— Literary Hub, Literary Hub, 22 Sep. 2026

Definition of rational

Adjective

Whatever a company decides today may not remain sensible six months from now.

— Vinit Sahni, Forbes.com, 23 Sep. 2026
Oakley has directed a new interpretation of the book, starring Daisy Edgar-Jones as the sensible Elinor Dashwood and Esmé Creed-Miles as her more emotive sister, Marianne.

— Rebecca Mead, New Yorker, 21 Sep. 2026

Definition of sensible

Adjective

Recovery, when it’s required, is faster and more coherent because all stakeholders are working from the same operational picture.

— Abha Dogra, Forbes.com, 29 Sep. 2026
By entangling 30 logical qubits in a single, coherent quantum state, Infleqtion has validated the core architecture of its Sqale hardware and Superstaq software, on its roadmap to deliver 100 logical qubits by 2028.

— Prabhat Ranjan Mishra, Interesting Engineering, 25 Sep. 2026

Definition of coherent

Adjective

The menu is no phonebook, and what has made the cut is well-justified.

— Kat Chen, Condé Nast Traveler, 21 Sep. 2026
Muslims can collectively work toward that goal by electing anti-Israel candidates, Spencer explained, so giving zakat in hopes of furthering the Palestinian cause is considered justified.

— Mia Cathell, The Washington Examiner, 20 Sep. 2026

Definition of justified

Browse Nearby Words

well-fixed

well-founded

well-groomed

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Style

“Well-founded.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/well-founded. Accessed 1 Oct. 2026.

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Synonyms of well-founded

adjective

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