talus vs os

talus and os both are nouns.

Word	Noun	Adjective	Verb	Adverb
talus	Yes	No	No	No
os	Yes	No	No	No

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

talus: the bone in the ankle that articulates with the leg bones to form the ankle joint
os: rigid connective tissue that makes up the skeleton of vertebrates

Other hypernyms of talus include bone.

talus (noun)	os (noun)
the bone in the ankle that articulates with the leg bones to form the ankle joint	rigid connective tissue that makes up the skeleton of vertebrates
a sloping mass of loose rocks at the base of a cliff	a mouth or mouthlike opening