luxuriousness vs luxury

luxuriousness and luxury both are nouns.

Word	Noun	Adjective	Verb	Adverb
luxuriousness	Yes	No	No	No
luxury	Yes	No	No	No

As nouns, luxuriousness and luxury are synonyms defined as:

Other synonyms of luxuriousness include opulence, sumptuousness.

luxuriousness (noun)	luxury (noun)
wealth as evidenced by sumptuous living	something that is an indulgence rather than a necessity
	the quality possessed by something that is excessively expensive
	wealth as evidenced by sumptuous living