wiseacre Meaning, Definition & Usage

  1. noun an upstart who makes conceited, sardonic, insolent comments
    wise guy; wisenheimer; weisenheimer; smart aleck.

WordNet

Wise"a*cre noun
Etymology
OD. wijssegger or G. weissager a foreteller, prophet, from weissagen to foretell, to prophesy, OHG. wissagn, corrupted (as if compounded of the words for wise and say) fr. wizzagn, fr. wizzag a prophet, akin to AS. witiga, witga, from the root of E. wit. See Wit, v.
Definitions
  1. A learned or wise man. Obs.
    Pythagoras learned much . . . becoming a mighty wiseacre. Leland.
  2. One who makes undue pretensions to wisdom; a would-be-wise person; hence, in contempt, a simpleton; a dunce.

Webster 1913