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

Synonyms & Antonyms for infallible



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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 What possession made of atoms needs an infallible chain of ownership - a blockchain - or NFT - more than an autograph? Charlie Fink, Forbes, "This Week In XR: Apple And Epic Sharpen Their Knives," 9 Apr. 2021 In humanity there is fallibility, even to those who present themselves as infallible, perhaps even more so for such people. Olivia F. Scott, Essence, "What The Derrick Jaxn Fallout Means To Black Women Who Supported Him," 26 Mar. 2021 Scenes set in the storied FAME Studios in Muscle Shoals, Ala., reveal a woman with infallible insight, whose clarity of artistic vision can be intimidating to her collaborators. Judy Berman, Time, "Genius: Aretha Is a Lavish, Lively Showstopper That Hits a Few False Notes," 19 Mar. 2021 Atlanta is hardly infallible, still a game under .500. Chris Fedor, cleveland, "Playoffs? Cleveland Cavaliers come out of the break thinking big, but how likely is it after back-to-back blowout losses?," 15 Mar. 2021 Democrats don’t need to pretend that every Democrat who ever held office was infallible. Rahm Emanuel, WSJ, "Democrats Need an 11th Commandment," 1 Mar. 2021 Another pamphlet even targets the queen (Golda Rosheuvel) and her judgment, which is considered near-infallible among the high-society set. Shirley Li, The Atlantic, "The Era of Gossip Isn’t Over," 22 Jan. 2021 There is no one on the face of the Earth that has a memory that’s infallible. Monivette Cordeiro,, "Mom questions dropped charges in 1-year-old’s hot-car death in Orlando: ‘All I’m asking for is justice’," 31 Dec. 2020 Parents also should know that the new technologies being used to evaluate students aren’t infallible. Lisa Ward, WSJ, "Data Privacy in the Age of Online Learning," 8 Dec. 2020

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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Time Traveler for infallible

Time Traveler

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

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Statistics for infallible

Last Updated

17 Apr 2021

Cite this Entry

“Infallible.” Dictionary, Merriam-Webster, Accessed 19 Apr. 2021.

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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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