stern vs ass

stern and ass both are nouns.

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

As nouns, stern and ass are synonyms defined as:

stern (noun)	ass (noun)
the rear part of a ship	slang for sexual intercourse
the fleshy part of the human body that you sit on	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

stern (adjective)	ass (adjective)
severe and unremitting in making demands
not to be placated or appeased or moved by entreaty
of a stern or strict bearing or demeanor; forbidding in aspect
severely simple