aristocracy vs noblesse

aristocracy and noblesse both are nouns.

Word	Noun	Adjective	Verb	Adverb
aristocracy	Yes	No	No	No
noblesse	Yes	No	No	No

As nouns, noblesse is a hyponym of aristocracy; that is, noblesse is a word with a more specific, narrower meaning than aristocracy:

Other hyponyms of aristocracy include baronage, peerage, baronetage, knighthood, samurai.

aristocracy (noun)	noblesse (noun)
a privileged class holding hereditary titles	members of the nobility (especially of the French nobility)
the most powerful members of a society	the state of being of noble birth