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

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Other Words from infallible

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

Synonyms & Antonyms for infallible


unerring, unfailing



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Did You Know?

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

Belichick’s genius lies not in being infallible, but in the fact that everything is fixable for him. Globe Staff,, "Bill Belichick’s true genius lies in course corrections," 5 Sep. 2019 If someone can explain why Dickerson really isn’t a .300-plus hitter with an infallible stroke, please step forward. Bruce Jenkins,, "Giants lose, but festive mood is refreshing," 20 July 2019 The astronaut mold was supposed to produce infallible supermen full of the right stuff. David Whitley,, "Buzz Aldrin landed on the moon, but his long, strange trip began after Apollo 11," 10 May 2019 To suggest Disney is infallible while Sony is incompetent is a level of corporate investment that feels gross. Richard Newby, The Hollywood Reporter, "How 'Spider-Man' Divorce Shows Ugly Side of Fandom," 22 Aug. 2019 Falling corporate profitability is considered a strong, though not infallible, indicator of an approaching recession. Stephen Gandel, CBS News, "Fading corporate profits heighten U.S. recession fears," 22 Aug. 2019 While these sorts of statements are usually infallible in their ability to induce groans from the team's supporters, there is undeniable credence to Klopp's claims., "Premier League Fantasy Football: 10 Under the Radar Picks for Your 2019/20 Squad," 25 July 2019 There is, however, no great and infallible arbiter of literary merit. Hermione Hoby, The New Yorker, "What Does It Mean to Be a “Real” Writer?," 3 July 2019 Then, as now, this was no mean feat; after all, previous bishops of Rome had rarely been as infallible as later dogma insisted. The Economist, "The most scandalous popes in history," 29 June 2019

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.

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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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Statistics for infallible

Last Updated

18 Sep 2019

Look-up Popularity

Time Traveler for infallible

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

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More Definitions for infallible



English Language Learners Definition of infallible

: not capable of being wrong or making mistakes : not fallible
: certain to work properly or succeed


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

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Comments on infallible

What made you want to look up infallible? Please tell us where you read or heard it (including the quote, if possible).


to make a temporary encampment

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