Boyd’s Bible Dictionary:
(bone-breaker). An unclean bird; the lammergeir, or bearded vulture (Lev. 11:13; Deut. 14:12).
Concise Bible Dictionary:
The Hebrew is peres, which signifies “breaking,” and ossifrage signifies “bone breaker.” This has led to the identifying the bird with the one now known as the Lammergeier (Gypaetus barbatus), which is a species of vulture, though it has the appearance of an eagle, its neck being covered with feathers. It attacks a carcass when the vultures have finished: picks the bones, and then breaks them to feed upon the marrow. It does this by carrying them up to a height and letting them fall upon a stone or rock till they break. The shells of tortoises are broken in the same way by them. In the Levitical economy it was an unclean bird (Lev. 11:13; Deut. 14:12).
Lammergeier – Bearded Vulture