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 SFA insisted their officials "are not infallible".

From BBC • May 15, 2026

They are never infallible or immune to misjudgment.

From Slate • Feb. 16, 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

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

In the United States the FBI, which often has to extract DNA in criminal cases, considers the test, when done with the latest technology, infallible.

From "Endgame" by Frank Brady

Vocabulary lists containing infallible

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"The Odyssey" by Homer, Books 1–7

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