A muscle which surrounds, and by its contraction tends to close, a natural opening; as, the sphincter of the bladder
{i} ring-shaped muscle whose function is to constrict or close the body opening or passage which it surrounds
Refers to a muscle that surrounds and closes an opening When an ostomy is performed, the sphincter that allows for control of output is bypassed An ostomy does not have a sphincter
A sphincter is a ring of muscle that surrounds an opening to the body and that can tighten to close this opening. the anal sphincter. a muscle that surrounds an opening in your body, and can become tight in order to close the opening (from sphingein )