ornament vs adorn

ornament is a noun but adorn is not a noun.

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

As verbs, ornament and adorn are synonyms defined as:

ornament and adorn: make more attractive by adding ornament, colour, etc.

Other synonyms of ornament include beautify, decorate, embellish, grace.

As verbs, adorn is a hypernym of ornament; that is, adorn is a word with a broader meaning than ornament:

Other hypernyms of ornament include beautify, deck, decorate, embellish, grace.

ornament (noun)	adorn (noun)
something used to beautify

ornament (verb)	adorn (verb)
make more attractive by adding ornament, colour, etc.	make more attractive by adding ornament, colour, etc.
be an ornament to	furnish with power or authority; of kings or emperors
	be beautiful to look at