yes-man vs flunky

yes-man and flunky both are nouns.

Word	Noun	Adjective	Verb	Adverb
yes-man	Yes	No	No	No
flunky	Yes	No	No	No

As nouns, yes-man and flunky are synonyms defined as:

Other synonyms of yes-man include flunkey, stooge.

yes-man (noun)	flunky (noun)
a person of unquestioning obedience	a person of unquestioning obedience
	a male servant (especially a footman)