piece of tail vs piece of ass

piece of tail and piece of ass both are nouns.

Word	Noun	Adjective	Verb	Adverb
piece of tail	Yes	No	No	No
piece of ass	Yes	No	No	No

As nouns, piece of tail and piece of ass are synonyms defined as:

Other synonyms of piece of tail include ass, fuck, fucking, nookie, nooky, roll in the hay, screw, screwing, shag, shtup.

piece of tail (noun)	piece of ass (noun)
slang for sexual intercourse	slang for sexual intercourse