decor vs ornament

decor and ornament both are nouns.

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

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

decor: decoration consisting of the layout and furnishings of a livable interior
ornament: something used to beautify

Other hypernyms of decor include decoration, ornamentation.

decor (noun)	ornament (noun)
decoration consisting of the layout and furnishings of a livable interior	something used to beautify

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