in·​fal·​li·​ble | \ (ˌ)in-ˈfa-lə-bəl How to pronounce infallible (audio) \

Definition of infallible

1 : incapable of error : unerring an infallible memory
2 : not liable to mislead, deceive, or disappoint : certain an infallible remedy
3 : incapable of error in defining doctrines touching faith or morals

Other Words from infallible

infallibility \ (ˌ)in-​ˌfa-​lə-​ˈbi-​lə-​tē How to pronounce infallible (audio) \ noun
infallibly \ (ˌ)in-​ˈfa-​lə-​blē How to pronounce infallible (audio) \ adverb

Synonyms & Antonyms for infallible



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Watch out when you hear about infallible predictions, an infallible plan, an infallible cure, or even infallible lip gloss. Infallible isn't a claim that scientists, engineers, and doctors like to make, so you're probably getting better information when the word not comes first. You may have heard the phrase "papal infallibility", which refers to the official position of the Roman Catholic church, adopted in the 19th century, that certain solemn statements made by a Pope about faith or morals were not to be questioned. Popes since then have been careful not to make many of these statements.

Examples of infallible in a Sentence

I never claimed to be infallible. There is no infallible remedy to these problems.
Recent Examples on the Web His Orioles teammates, however, have combined for four hits in those situations, creating an offensive impasse that requires the pitching staff to be infallible. Andy Kostka, Baltimore Sun, 16 Apr. 2022 Finally, secret police and military elites, together with a corrupt bureaucracy, form the core of the political system headed by the infallible Putin, who is the undisputed charismatic leader glorified as the embodiment of Russia. Alexander Motyl, The Conversation, 30 Mar. 2022 The once-infallible party leader’s fall from grace was rapid and dramatic. Richard Collett, Smithsonian Magazine, 28 Mar. 2022 But more importantly, South Korean officials said, Kim used the launch and a crude, fake presentation of video and photos ​to demonstrate his infallible leadership to the long-suffering people of North Korea. Choe Sang-hun,, 31 Mar. 2022 Although South Carolina has dominated Division I since the tip-off of the 2021-22 season, not even the Gamecocks are infallible going into the tournament. New York Times, 14 Mar. 2022 Maybe in some parallel universe populated by infallible robot referees, Louisville still loses in overtime to North Carolina. Tim Sullivan, The Courier-Journal, 4 Feb. 2022 And for those about to compete, Biles is a role model — not for being infallible, but for being human. New York Times, 8 Feb. 2022 Offline authentication is not infallible, of course. Martin Ladstaetter, Forbes, 5 Jan. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infallible.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of infallible

15th century, in the meaning defined at sense 1

History and Etymology for infallible

Middle English, from Medieval Latin infallibilis, from Latin in- + Late Latin fallibilis fallible

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The first known use of infallible was in the 15th century

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Last Updated

29 Apr 2022

Cite this Entry

“Infallible.” Dictionary, Merriam-Webster, Accessed 19 May. 2022.

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More Definitions for infallible


in·​fal·​li·​ble | \ in-ˈfa-lə-bəl How to pronounce infallible (audio) \

Kids Definition of infallible

1 : not capable of being wrong an infallible memory
2 : certain to succeed : sure an infallible remedy

Other Words from infallible

infallibly \ -​blē \ adverb

More from Merriam-Webster on infallible

Nglish: Translation of infallible for Spanish Speakers

Britannica English: Translation of infallible for Arabic Speakers


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