obscenity vs piece of tail

obscenity and piece of tail both are nouns.

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

obscenity (noun)	piece of tail (noun)
an obscene act	slang for sexual intercourse
the trait of behaving in an obscene manner
an offensive or indecent word or phrase