jackass Meaning, Definition & Usage

  1. noun a man who is a stupid incompetent fool
    goof; cuckoo; fathead; goose; bozo; zany; twat; goofball.
  2. noun male donkey
    jack.

WordNet

Jack"ass` noun
Etymology
2d jack + ass.
Definitions
  1. The male ass; a donkey.
  2. A conceited dolt; a perverse blockhead.

Webster 1913