noun
keel (bird bone); carina
Anatomical term for the ridge on the sternum of birds and some other animals where flight muscles attach.
鳥の竜骨突起は飛ぶために発達している。
The keel of birds is developed for flight.
Compound of 竜骨 (ryūkotsu, 'keel of a ship') and 突起 (tokki, 'protrusion'), referring to the keel-like ridge on the sternum.