Lunar \Lu"nar\, n.

1. (Astron.) A lunar distance.

2. (Anat.) The middle bone of the proximal series of the carpus; -- called also semilunar, and intermedium.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Semilunar \Sem`i*lu"nar\, n. (Anat.) The semilunar bone.

Source: Webster's Revised Unabridged Dictionary (1913)
 

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, 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.

Source: Webster's Revised Unabridged Dictionary (1913)