male aristocrat vs Lord

male aristocrat and Lord both are nouns.

Word	Noun	Adjective	Verb	Adverb
male aristocrat	Yes	No	No	No
Lord	Yes	No	No	No

As nouns, Lord is a hyponym of male aristocrat; that is, Lord is a word with a more specific, narrower meaning than male aristocrat:

Other hyponyms of male aristocrat include cavalier, chevalier, knight, noble, nobleman, Sir.

male aristocrat (noun)	Lord (noun)
a man who is an aristocrat	a titled peer of the realm
	terms referring to the Judeo-Christian God