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Showing results for infallible. Search instead for infallible/3.
Definitions

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.

They are never infallible or immune to misjudgment.

From Slate • Feb. 16, 2026

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

From BBC • Feb. 7, 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

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

From MarketWatch • Dec. 12, 2025

Even the trees were not as infallible a guide as they might have hoped, for there were wooded islands in the lake, and wide areas ashore where no trees grew.

From "A Dance with Dragons" by George R. R. Martin