bladder sphincter

English Thesaurus

1. the sphincter muscle of the urinary bladder; made up of a thickened muscular layer of bladder around the urethral opening (noun.body)

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

part meronym	:	urinary bladder,
definition	:	a membranous sac for temporary retention of urine (noun.body)