Infallible
Pronunciation : In*fal"li*ble
Part of Speech : a.
Etymology : [Pref. in- not + fallible: cf. F. infallible.]
Definition : 1. Not fallible; not capable of erring; entirely exempt from liability to mistake; unerring; inerrable. Dryden.
2. Not liable to fail, deceive, or disappoint; indubitable; sure; certain; as, infallible evidence; infallible success; an infallible remedy. To whom also he showed himself alive, after his passion, by many infallible proofs. Acts i. 3.
3. (R. C. Ch.)
Defn: Incapable of error in defining doctrines touching faith or morals. See Papal infallibility, under Infallibility.
Source : Webster's Unabridged Dictionary, 1913