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Added 10 October 2026

infallible

/ɪnˈfælɪbəl/ noun

Latin root: īnfallibilis Wiktionary

noun Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about infallible at Wordnik → Where our words come from →

A person who, or an object or process that, is taken as being infallible.

adjective

Without fault or weakness; incapable of error or fallacy.
He knows about many things, but even he is not infallible.
Certain to produce the intended effect; sure.
Try this infallible cure for hiccups.
Certain to result from a specific cause; inevitable.

Origin

From Medieval Latin īnfallibilis, from Latin in- + fallibilis. Compare French infaillible. By surface analysis, in- + fallible.

From Wiktionary, via Kaikki.org (CC BY-SA)

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