INFALLIBLE Synonyms: 27 Similar and Opposite Words

infallible

adjective

(ˌ)in-ˈfa-lə-bəl

Definition of infallible

as in unerring

not being or likely to be wrong a teacher with an infallible memory for names

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in reliable

not likely to fail an infallible cure for hiccups

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 infallible Corporate governance solutions rarely come in the form of universal, infallible prescriptions. — Jeffrey Sonnenfeld, Fortune, 6 July 2026 Instead, he was treated as an infallible saint. — Ian Miller Outkick, FOXNews.com, 22 June 2026 How democracy works Congress is not infallible, and the Constitution does not suggest that its judgment should automatically prevail over presidential will. — Stephanie A, The Conversation, 22 June 2026 The hard part is building systems that make those signals legible to the people who have to act on them — who have to order more stock, shift production, or reposition inventory based on what the model says, knowing that the model is not infallible and that the cost of being wrong is real. — Karen Koehler, Charlotte Observer, 17 June 2026 See All Example Sentences for infallible

Recent Examples of Synonyms for infallible

Adjective

Dean has an unerring sense about how to let her voice glide to the cumulus layer and back again, without remotely ever going over the top.

— Chris Willman, Variety, 17 July 2026
While there is undeniable star power, and an unerring ability to get the job done, England will have opportunities to make a mark of their own.

— Stuart James, New York Times, 12 July 2026

Definition of unerring

Adjective

Tech firms used to be reliable stocks, reporting high profits and juicy margins, but the race to build AI data centers and train new models has changed the landscape.

— Ryan Whitwam, ArsTechnica, 23 July 2026
Digital footprint analysis is becoming one of the most reliable tools in credit risk.

— Artem Lalaiants, Forbes.com, 23 July 2026

Definition of reliable

Adjective

Despite Clarity’s choppy obstacle course, the tedious and frustrating tradition of counting votes and lining up bipartisan yeahs, Member by Member, is a tactic the crypto industry has time to employ and perfect.

— Cleve Mesidor, Forbes.com, 21 July 2026
The dinner theme is Paris, which is perfect for Joy, or at least should be.

— Rafaela Bassili, Vulture, 21 July 2026

Definition of perfect

Adjective

Their reach was owed not just to the nine-member unit’s technical excellence and versatility but also their endless supply of positivity, of psychedelic Black power characterized by its leader’s unfailing belief in a beautiful tomorrow.

— Craig Jenkins, Vulture, 9 June 2026
His unfailing commitment to civilian authority gave time for government institutions to sink roots, and established norms that gelled into the professional ethos of our military today.

— Kori Schake, The Atlantic, 22 Mar. 2026

Definition of unfailing

Adjective

Young was flawless until the final hole, his tee shot finding a pot bunker.

— Doug Ferguson, Los Angeles Times, 19 July 2026
The Spaniards have taken the air out of the balls, played keep-away, erected a flawless defensive fortress, and hijacked tournament brackets from far more direct teams like France and England.

— Filip Bondy, New York Daily News, 19 July 2026

Definition of flawless

Adjective

Yesavage, after tearing through college and rapidly ascending the minor leagues last year, still wasn’t entirely sure if his release point would play in the big leagues.

— Mitch Bannon, New York Times, 20 July 2026
And, of course, nothing here can happen unless the city feels sure such a plan wouldn’t result in a credit-ratings downgrade.

— The Editorial Board, Chicago Tribune, 19 July 2026

Definition of sure

Browse Nearby Words

infallibility

infallible

infallibly

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Cite this Entry

Style

“Infallible.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/infallible. Accessed 26 Jul. 2026.

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Synonyms of infallible

adjective

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