infallible

adjective

(ˌ)in-ˈfa-lə-bəl How to pronounce infallible (audio)
Definition of infalliblenext
1
as in unerring
not being or likely to be wrong a teacher with an infallible memory for names

Synonyms & Similar Words

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Antonyms & Near Antonyms
2
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 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 Similar to human drivers, Zoox's AI and safety systems aren't infallible, but the test ride vehicle didn't exhibit any odd behaviors that seemed problematic or scary for occupants. — Charles Singh, USA Today, 11 May 2026 Look For What's Missing From The Data Strong marketing leaders know data is directional, not infallible. — Expert Panel®, Forbes.com, 23 June 2026 See All Example Sentences for infallible
Recent Examples of Synonyms for infallible
  1. unerring
  2. reliable
  3. perfect
  4. unfailing
  5. flawless
  6. sure
Adjective
  • The presence of another Golden Boot contender, the unerring Erling Haaland, means Norway is favored to progress against the Ivory Coast, although this is its first knockout match in 28 years.
    — David Hickey, NBC news, 30 June 2026
  • Ditto Hugh Jackman’s unerring performance — perhaps his finest dramatic work yet — as a savage, unfeeling thug and unrepentant murderer and thief.
    — Randy Myers, Mercury News, 18 June 2026
Definition of unerring
Adjective
  • Andrews, a lifelong resident of Red Hook Houses West, said the community has waited long enough for a reliable pool.
    — Hannah Kliger, CBS News, 2 July 2026
  • No reliable figures are available for battlefield casualties in the war.
    — Hanna Arhirova, Los Angeles Times, 2 July 2026
Definition of reliable
Adjective
  • In comparison, the Sparks, without an offensive rebound until the end of the third quarter, were forced to make perfect shots, though that was far from the team’s grasp.
    — Liana Handler, Los Angeles Times, 7 July 2026
  • While no missile defense system offers perfect protection, modern layered architectures have significantly improved the ability to detect, track, and intercept increasingly sophisticated threats.
    — Kaif Shaikh, Interesting Engineering, 6 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
  • Because autonomous agents execute end-to-end business logic, deployment requires a flawless blend of operational domain expertise (business) and systemic oversight (IT).
    — Barney Krishnan, Forbes.com, 1 July 2026
  • The fluffy brush made with vegan bristles is angled for flawless foundation application.
    — Tessa Petak, InStyle, 27 June 2026
Definition of flawless
Adjective
  • More the former than the latter, sure, but both men are not overly pleased at the way they’re being treated.
    — Erik Kain, Forbes.com, 6 July 2026
  • Although astronomers are pretty sure there is a neutron star in the heart of the remnant based on indirect evidence, no pulsar radio emissions have yet been detected.
    — Keith Cooper, Space.com, 6 July 2026
Definition of sure

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Cite this Entry

“Infallible.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/infallible. Accessed 7 Jul. 2026.

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More from Merriam-Webster on infallible

Nglish: Translation of infallible for Spanish Speakers

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