Wiktionary
lunate bone
n. (context anatomy English) One of the carpal bones of the wrist.
WordNet
lunate bone
n. one of the eight small wrist bones [syn: semilunar bone, os lunatum]
Wikipedia
Lunate bone
The lunate bone (semilunar bone) is a carpal bone in the human hand. It is distinguished by its deep concavity and crescentic outline. It is situated in the center of the proximal row carpal bones, which lie between the ulna and radius and the hand. The lunate carpal bone is situated between the lateral scaphoid bone and medial triquetral bone.