also: ついこつ · つちぼね
noun
malleus; hammer (ear bone)
Anatomical term for the hammer-shaped bone in the middle ear. Used in medical and biological contexts.
槌骨は耳小骨の一つで、鼓膜の振動を内耳に伝える。
The malleus is one of the auditory ossicles and transmits vibrations from the eardrum to the inner ear.
From 槌 (つち, 'hammer') + 骨 (こつ, 'bone'), referring to the hammer-like shape of the malleus.