锤骨

锤骨	chuí gǔ	malleus or hammer bone of middle ear
锤	chuí	hammer / to hammer into shape / weight (e.g. of a steelyard or balance) / to strike with a hammer
锤	chuí	variant of 锤
骨	gū	used in 骨碌碌 / used in 骨碌
骨	gǔ	bone