wisenheimer

1. (chiefly US, informal, mildly humorous) A self-assertive and arrogant person; a know-it-all or smart aleck.Examples: "There was an auto salesman in here yesterday that claimed you could always tell a fellow's class by the car he drove, but I says to him, 'Don't be silly,' I says; 'the wisenheimers grab a look at a fellow's nails when they want to tell if he's a tin-horn or a real gent!"'"; ""It wasn’t until I read Mark Oppenheimer’s charming memoir that I had an apt description of my son: “…a smart aleck is a smart guy gone bad, a boy whose smartness is being used stupidly, while a wisenheimer actually lacks wisdom. He might not be cruel, he might not mean harm, but a wisenheimer is a smart guy you wish had a little less smarts.”"Synonyms: wise guy, smart aleck, Buddha, clever clogs, clever dick, know-all, know-it-all, smart aleckUShumorousinformalmildly