[1] : The Collaborative International Dictionary of English v.0.48

wiseacre \wise"acre\, n. od. wijssegger or g. weissager a
   foreteller, prophet, from weissagen to foretell, to prophesy,
   ohg. wimacssag?n, corrupted as if compounded of the words
   for wise and say fr. wimaczzag?n, fr. wimaczzag? a
   prophet, akin to as. wimactiga, wimactga, from the root
   of e. wit. see wit, v.
   1913 webster
   1. a learned or wise man. obs.
      1913 webster

            pythagoras learned much . . . becoming a mighty
            wiseacre.                             --leland.
      1913 webster

   2. one who makes undue pretensions to wisdom; a would-be-wise
      person; hence, in contempt, a simpleton; a dunce.
      1913 webster
see also:
wit 

[2] : WordNet (r) 2.0

wiseacre
     n : an upstart who makes conceited, sardonic, insolent comments
         syn: wise guy, smart aleck, wisenheimer, weisenheimer
see also:
wise guy smart aleck wisenheimer weisenheimer 

Wiseacre >> W Words
Wiseacre, definition of term: Wiseacre
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