Also found in: Thesaurus, Medical, Encyclopedia, Wikipedia.
Switch to new thesaurus
|Noun||1.||sphincter ani - the sphincter muscle of the anus|
anus - the excretory opening at the end of the alimentary canal
anatomical sphincter, sphincter, sphincter muscle - a ring of muscle that contracts to close an opening
musculus sphincter ani externus - an external ring of striated muscle surrounding the anus
musculus sphincter ani internus - an internal ring of smooth muscle formed by circular fibers of the rectum