Sphinc´ter, n. An annular muscle constricting or closing a natural orifice; especially, sphincter ani.
Spi´nal, a. Relating to the backbone.
Spina´lis, a. for n. Name of a certain muscle of the back.
Spine, n. Backbone. Also, any sharp projecting point of bone or horn.
Spinose´ or Spi´nous, a. Sometimes said of a mucronate feather.
Splanch´nic, a. Visceral.
Splanchnol´ogy, n. Science or study of the viscera.
Spleen, n. A deep red, soft, spongy, ductless and extremely vascular, abdominal organ of uncertain function.
Sple´nial, a. Name of a certain element of the mandible.
Sple´nius, a. for n. A certain cervical muscle.