gentleman's gentleman vs valet

gentleman's gentleman and valet both are nouns.

Word	Noun	Adjective	Verb	Adverb
gentleman's gentleman	Yes	No	No	No
valet	Yes	No	Yes	No

As nouns, gentleman's gentleman and valet are synonyms defined as:

gentleman's gentleman and valet: a manservant who acts as a personal attendant to his employer

Other synonyms of gentleman's gentleman include gentleman, man, valet de chambre.

gentleman's gentleman (noun)	valet (noun)
a manservant who acts as a personal attendant to his employer	a manservant who acts as a personal attendant to his employer

gentleman's gentleman (verb)	valet (verb)
	serve as a personal attendant to