furcula vs os

furcula and os both are nouns.

As nouns, os is a hypernym of furcula; that is, os is a word with a broader meaning than furcula:

Other hypernyms of furcula include bone.

furcula (noun)	os (noun)
a forked bone formed by the fusion of the clavicles of most birds	a mouth or mouthlike opening
	rigid connective tissue that makes up the skeleton of vertebrates