sumptuousness vs wealthiness

sumptuousness and wealthiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
sumptuousness	Yes	No	No	No
wealthiness	Yes	No	No	No

As nouns, wealthiness is a hypernym of sumptuousness; that is, wealthiness is a word with a broader meaning than sumptuousness:

sumptuousness: wealth as evidenced by sumptuous living
wealthiness: the state of being rich and affluent; having a plentiful supply of material goods and money

Other hypernyms of sumptuousness include wealth.

sumptuousness (noun)	wealthiness (noun)
the quality possessed by something that is excessively expensive	the state of being rich and affluent; having a plentiful supply of material goods and money
wealth as evidenced by sumptuous living