Definitions

from The American Heritage® Dictionary of the English Language, 4th Edition

  • adj. Incapable of erring: an infallible guide; an infallible source of information.
  • adj. Incapable of failing; certain: an infallible antidote; an infallible rule.
  • adj. Roman Catholic Church Incapable of error in expounding doctrine on faith or morals.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • adj. Without fault or weakness; incapable of error or fallacy.
  • adj. certain, sure.

from the GNU version of the Collaborative International Dictionary of English

  • adj. Not fallible; not capable of erring; entirely exempt from liability to mistake; unerring; inerrable.
  • adj. Not liable to fail, deceive, or disappoint; indubitable; sure; certain
  • adj. Incapable of error in defining doctrines touching faith or morals. See Papal infallibility, under Infallibility.

from The Century Dictionary and Cyclopedia

  • Not fallible in knowledge, judgment, or opinion; exempt from fallacy or liability to error; unerring.
  • Unfailing in character or effect; exempt from uncertainty or liability to failure; absolutely trustworthy.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • adj. incapable of failure or error

Etymologies

Middle English, from Medieval Latin īnfallibilis : Latin in-, not; see in-1 + Medieval Latin fallibilis, fallible; see fallible.
(American Heritage® Dictionary of the English Language, Fourth Edition)
From Medieval Latin infallibilis, from Latin in- + fallibilis. Compare French infaillible. (Wiktionary)

Examples

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Comments

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  • I saw the pope in the woods the other day (I was frolicing on my way to damnation) and I'm like, "Dude, where're your little red shoes?" And the pope just muttered, "Damn bear..."

    May 6, 2008

  • This is correct. And the year was 1854, I believe. (I always thought it was 1864, but Wikipedia says I'm wrong. Hmph.) It is shocking to me--well, maybe not actually shocking; more like surprising--how many Catholics don't know about the ex cathedra thing, or when was the last time the pope sat in it while loudly declaiming something. Non-Catholics I would expect not to know about it because, you know, it's easier just to say the lovely word infallible and be done with it. (It does give good mouthfeel.)

    Dude, the pontiff abolished limbo? I missed that memo.

    May 6, 2008

  • Indeed. Not that I've been keeping serious track, But I think the last time that happened was over a century ago, when the pontiff at the time weighed in on the important doctrinal issue of the Immaculate Conception.

    A question which many non-catholics (and more than a few catholics) regularly confuse with the virgin birth of Christ.

    So, let's be clear, wordies. The doctrine of the Immaculate Conception states that Mary, mother of Jesus, was born free of original sin, that unsightly blemish which besmirches the soul of us lesser mortals at birth. It has nothing whatsoever to do with her state of virginity or otherwise at the conception of Jesus. The 'conception' in 'Immaculate Conception' refers to that of Mary, not Jesus.

    As the pope was sitting in his infallible chair when he explained this, Catholics are expected to believe it. And to go to mass on December 8th to celebrate it.

    Non-Catholics (see heathen or pagan) may believe whatever they like as they frolic on the road to their damnation.

    In other news, Pope Rat-zinger recently abolished limbo, but reopened hell. But I don't think he was sitting in the infallibility chair at the time.

    May 6, 2008

  • only when he speaks ex cathedra, actually.

    May 6, 2008

  • Did you know that The Pope was infallible?

    May 6, 2008