anatomical sphincter vs sphincter muscle

anatomical sphincter and sphincter muscle both are nouns.

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

As nouns, anatomical sphincter and sphincter muscle are synonyms defined as:

anatomical sphincter and sphincter muscle: a ring of muscle that contracts to close an opening

Other synonyms of anatomical sphincter include sphincter.

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