What is "semilunar bone"

Semilunar \Sem`i*lu"nar\, a. Shaped like a half moon.

Semilunar bone (Anat.), a bone of the carpus; the lunar. See Lunar, n.

Semilunar valves, or Sigmoid valves (Anat.), the valves at the beginning of the aorta and of the pulmonary artery which prevent the blood from flowing back into the ventricle.

n. lunate bone

n. one of the eight small wrist bones [syn: lunate bone, os lunatum]