(Anatomie) Muscle annulaire autour d'un canal naturel.
ETYM New Lat., from sphingein to bind tight.
A ring of muscle that contracts to close an opening; SYN. anatomical sphincter, sphincter muscle.
Ringlike muscle closing body passage.
Ring of muscle found at various points in the alimentary canal, which contracts and relaxes to control the movement of food. The pyloric sphincter, at the base of the stomach, controls the release of the gastric contents into the duodenum. After release the sphincter contracts, closing off the stomach.