jackass vs ass

jackass and ass both are nouns.

Word	Noun	Adjective	Verb	Adverb
jackass	Yes	No	No	No
ass	Yes	No	No	No

As nouns, ass is a hypernym of jackass; that is, ass is a word with a broader meaning than jackass:

jackass: male donkey
ass: hardy and sure-footed animal smaller and with longer ears than the horse

jackass (noun)	ass (noun)
male donkey	slang for sexual intercourse
a man who is a stupid incompetent fool	hardy and sure-footed animal smaller and with longer ears than the horse
	the fleshy part of the human body that you sit on
	a pompous fool