muscle builder vs muscleman

muscle builder and muscleman both are nouns.

Word	Noun	Adjective	Verb	Adverb
muscle builder	Yes	No	No	No
muscleman	Yes	No	No	No

As nouns, muscle builder and muscleman are synonyms defined as:

muscle builder and muscleman: someone who does special exercises to develop a brawny musculature

Other synonyms of muscle builder include bodybuilder, muscle-builder, musclebuilder.

muscle builder (noun)	muscleman (noun)
someone who does special exercises to develop a brawny musculature	a bully employed as a thug or bodyguard
	someone who does special exercises to develop a brawny musculature