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

[Middle English, from Medieval Latin īnfallibilis : Latin in-, not; see in-1 + Medieval Latin fallibilis, fallible; see fallible.]

in·fal′li·bil′i·ty, in·fal′li·ble·ness n.
in·fal′li·bly adv.
بِعصْمة عن الخَطأ، بنزاهَه
óhjákvæmilega, örugglega


[ɪnˈfæləblɪ] ADV (= unfailingly) → infaliblemente; (= predictably) → indefectiblemente


advunfehlbar; workfehlerfrei


[ɪnˈfæləblɪ] advinfallibilmente
she's infallibly correct → ha sempre ragione
he infallibly arrives just as we are sitting down to eat → arriva puntualmente quando stiamo per sederci a tavola


(inˈfӕləbl) adjective
1. (of a person or his judgement etc) never making a mistake.
2. (of a remedy etc) always successful. infallible cures.
inˌfalliˈbility noun
inˈfallibly adverb
References in classic literature ?
In short, Uncas and his father became converts to his way of thinking, abandoning their own previously expressed opinions with a liberality and candor that, had they been the representatives of some great and civilized people, would have infallibly worked their political ruin, by destroying forever their reputation for consistency.
I reflected acutely that the sense of such differences, such superiorities of quality, always, on the part of the majority--which could include even stupid, sordid headmasters-- turn infallibly to the vindictive.
Let the most absent-minded of men be plunged in his deepest reveries--stand that man on his legs, set his feet a-going, and he will infallibly lead you to water, if water there be in all that region.
But mark: aloft there, at the three mast heads, stand three men intent on spying out more whales, which, if caught, infallibly will again soil the old oaken furniture, and drop at least one small grease-spot somewhere.
My spirits infallibly rise in proportion to the outward dreariness.
For, he contended with himself that it was impossible to foresee what that lady might pretend next; and he felt assured that if she should take it into her brightly ornamented head to pretend that she had seen him do a murder and afterwards flay the victim, she would infallibly go through with it until the play was played out.
Let him forsake a decent craft that he may pursue the gentilities of a profession to which nature never called him, and his religion will infallibly be the worship of blessed Chance, which he will believe in as the mighty creator of success.
It was very tiring and slow work, yet I did visibly gain ground; and as we drew near the Cape of the Woods, though I saw I must infallibly miss that point, I had still made some hundred yards of easting.
I was assured that, a year or two before my arrival, Flimnap would infallibly have broke his neck, if one of the king's cushions, that accidentally lay on the ground, had not weakened the force of his fall.
And because our reasonings are never so clear or so complete during sleep as when we are awake, although sometimes the acts of our imagination are then as lively and distinct, if not more so than in our waking moments, reason further dictates that, since all our thoughts cannot be true because of our partial imperfection, those possessing truth must infallibly be found in the experience of our waking moments rather than in that of our dreams.
Frequent war and constant apprehension, which require a state of as constant preparation, will infallibly produce them.
A local spirit will infallibly prevail much more in the members of Congress, than a national spirit will prevail in the legislatures of the particular States.