jenny vs ass

jenny and ass both are nouns.

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

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

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

jenny (noun)	ass (noun)
female donkey	slang for sexual intercourse
	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