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.

For a while after that, they seemed totally infallible, a giant blue behemoth blocking out the light.

From BBC • May 6, 2026

They are never infallible or immune to misjudgment.

From Slate • Feb. 16, 2026

His pizzazz was a large measure of his appeal, along with his manufactured image as a shrewd businessman with a kingly touch and infallible judgment.

From Los Angeles Times • Jan. 4, 2026

To be sure, the “lipstick index” was never infallible, or even very popular, as far as economic theories go.

From MarketWatch • Dec. 12, 2025

But since in reality Big Brother is not omnipotent and the Party is not infallible, there is need for an unwearying, moment-to-moment flexibility in the treatment of facts.

From "1984" by George Orwell

Vocabulary lists containing infallible

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"The Odyssey" by Homer, Books 1–7

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