obscenity vs smuttiness

obscenity and smuttiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
obscenity	Yes	No	No	No
smuttiness	Yes	No	No	No

As nouns, smuttiness is a hyponym of obscenity; that is, smuttiness is a word with a more specific, narrower meaning than obscenity:

Other hyponyms of obscenity include dirtiness.

obscenity (noun)	smuttiness (noun)
an obscene act	obscenity in speech or writing
the trait of behaving in an obscene manner	the state of being dirty with soot
an offensive or indecent word or phrase