graffiti vs ornament

graffiti and ornament both are nouns.

Word	Noun	Adjective	Verb	Adverb
graffiti	Yes	No	No	No
ornament	Yes	No	Yes	No

As nouns, ornament is a hypernym of graffiti; that is, ornament is a word with a broader meaning than graffiti:

Other hypernyms of graffiti include decoration, ornamentation.

graffiti (noun)	ornament (noun)
a rude decoration inscribed on rocks or walls	something used to beautify

graffiti (verb)	ornament (verb)
	make more attractive by adding ornament, colour, etc.
	be an ornament to