infallible

[in-fal-uh-buhl] / ɪnˈfæl ə bəl /

ADJECTIVE

unerring, dependable

Synonyms

STRONGEST

authoritative flawless foolproof unbeatable

WEAK

acceptable accurate agreeable apodictic certain correct effective effectual efficacious efficient exact faultless handy helpful impeccable incontrovertible inerrable inerrant omniscient perfect positive reliable satisfactory satisfying sure surefire true trustworthy undeceivable unfailing unimpeachable unquestionable useful

Antonyms

WEAK

erring fallible faulty imperfect

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

That is not to say humanity is infallible.

From Slate • May 28, 2026

A lapse in judgment has sent the previously infallible industry visionary, with Agnes in tow, into self-imposed, self-described exile on Maui, where the Hopkinses have built a showstopper of a house.

From The Wall Street Journal • Apr. 17, 2026

But it does make clear that AI isn’t magic, nor are those who are making and marketing it infallible.

From Los Angeles Times • Mar. 26, 2026

They aren't infallible but they will increase the hassle factor for criminals.

From BBC • Feb. 7, 2026

When things are going well, as they generally are, it is an infallible mechanism.

From "The Lives of a Cell" by Lewis Thomas

Vocabulary lists containing infallible

The Vocabulary.com Top 1000

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"The Odyssey" by Homer, Books 1–7

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