'Jackass' definitions:

Definition of 'jackass'

From: WordNet
noun
A man who is a stupid incompetent fool [syn: fathead, goof, goofball, bozo, jackass, goose, cuckoo, twat, zany]
noun
Male donkey [syn: jack, jackass]

Definition of 'Jackass'

From: GCIDE

Synonyms of 'jackass'

From: Moby Thesaurus