diaphysis vs long bone

diaphysis and long bone both are nouns.

Word	Noun	Adjective	Verb	Adverb
diaphysis	Yes	No	No	No
long bone	Yes	No	No	No

As nouns, long bone is a hypernym of diaphysis; that is, long bone is a word with a broader meaning than diaphysis:

diaphysis: the main (mid) section of a long bone
long bone: in limbs of vertebrate animals: a long cylindrical bone that contains marrow

Other hypernyms of diaphysis include os longum.

diaphysis (noun)	long bone (noun)
the main (mid) section of a long bone	in limbs of vertebrate animals: a long cylindrical bone that contains marrow