retractor muscle vs muscle

retractor muscle and muscle both are nouns.

Word	Noun	Adjective	Verb	Adverb
retractor muscle	Yes	No	No	No
muscle	Yes	No	Yes	No

As nouns, muscle is a hypernym of retractor muscle; that is, muscle is a word with a broader meaning than retractor muscle:

retractor muscle: Any of various muscles that retract an organ or a body part.
muscle: one of the contractile organs of the body

Other hypernyms of retractor muscle include musculus.

retractor muscle (noun)	muscle (noun)
Any of various muscles that retract an organ or a body part.	possessing muscular strength
	authority or power or force (especially when used in a coercive way)
	one of the contractile organs of the body
	animal tissue consisting predominantly of contractile cells
	a bully employed as a thug or bodyguard

retractor muscle (verb)	muscle (verb)
	make one's way by force