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.

The statute "does not treat as infallible the EPA's judgement as to whether FIFRA's midbranding provision has been violated," she wrote.

From Barron's • Jun. 25, 2026

That is not to say humanity is infallible.

From Slate • May 28, 2026

The SFA insisted their officials "are not infallible".

From BBC • May 15, 2026

For the cubicle set, he was Kafka with an American accent and an infallible comic touch.

From The Wall Street Journal • Jan. 13, 2026

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

The Vocabulary.com Top 1000

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"The Odyssey" by Homer, Books 1–7

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