sphincter vs muscle

sphincter and muscle both are nouns.

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

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

Other hypernyms of sphincter include musculus.

sphincter (noun)	muscle (noun)
a ring of muscle that contracts to close an opening	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

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