calf bone vs fibula

calf bone and fibula both are nouns.

Word	Noun	Adjective	Verb	Adverb
calf bone	Yes	No	No	No
fibula	Yes	No	No	No

As nouns, calf bone and fibula are synonyms defined as:

calf bone and fibula: the outer and thinner of the two bones of the human leg between the knee and ankle

calf bone (noun)	fibula (noun)
the outer and thinner of the two bones of the human leg between the knee and ankle	the outer and thinner of the two bones of the human leg between the knee and ankle