physiological sphincter

English Thesaurus

1. a sphincter that is not recognizable at autopsy because its resting arrangement cannot be distinguished from adjacent tissue (noun.body)

hypernym	:	anatomical sphincter, sphincter, sphincter muscle,
definition	:	a ring of muscle that contracts to close an opening (noun.body)

hyponym	:	cardiac sphincter,
definition	:	the valve between the distal end of the esophagus and the stomach; the physiological sphincter at the esophagogastric junction (noun.body)