apatosaur vs sauropod

apatosaur and sauropod both are nouns.

Word	Noun	Adjective	Verb	Adverb
apatosaur	Yes	No	No	No
sauropod	Yes	No	No	No

As nouns, sauropod is a hypernym of apatosaur; that is, sauropod is a word with a broader meaning than apatosaur:

apatosaur: huge quadrupedal herbivorous dinosaur common in North America in the late Jurassic
sauropod: very large herbivorous dinosaur of the Jurassic and Cretaceous having a small head on a long neck and tail and five-toed limbs; largest known land animal

Other hypernyms of apatosaur include sauropod dinosaur.

apatosaur (noun)	sauropod (noun)
huge quadrupedal herbivorous dinosaur common in North America in the late Jurassic	very large herbivorous dinosaur of the Jurassic and Cretaceous having a small head on a long neck and tail and five-toed limbs; largest known land animal