Simple Definition of infallible
: not capable of being wrong or making mistakes : not fallible
: certain to work properly or succeed
Full Definition of infallible
infallibilityplay \-ˌfa-lə-ˈbi-lə-tē\ noun
infalliblyplay \-ˈfa-lə-blē\ adverb
Examples of infallible in a sentence
I never claimed to be infallible.
There is no infallible remedy to these problems.
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.
Origin and Etymology of infallible
Middle English, from Medieval Latin infallibilis, from Latin in- + Late Latin fallibilis fallible
First Known Use: 15th century
INFALLIBLE Defined for Kids
Seen and Heard
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