PRONUNCIATION: wī' zən-hī' mər
NOUN: Informal A smart aleck.
ETYMOLOGY: wise[sup]1[/sup] + German -enheimer (in such surnames as Oppenheimer).
The American Heritage® Dictionary of the English Language: Fourth Edition. 2000
Online Etymology Dictionary entry for wise:
In Play: Use this less-insulting, somewhat humorous word when Smart-ass is too strong and Wise-guy isn't quite strong enough.. . . Wise guy is attested from 1896, Amer.Eng.; wisecrack is from 1924. Wisenheimer, with mock Ger. or Yiddish surname suffix, first recorded 1904.