brontosaurus vs apatosaur

brontosaurus and apatosaur both are nouns.

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

As nouns, brontosaurus and apatosaur are synonyms defined as:

brontosaurus and apatosaur: huge quadrupedal herbivorous dinosaur common in North America in the late Jurassic

Other synonyms of brontosaurus include apatosaurus, Apatosaurus excelsus, brontosaur, thunder lizard.

brontosaurus (noun)	apatosaur (noun)
huge quadrupedal herbivorous dinosaur common in North America in the late Jurassic	huge quadrupedal herbivorous dinosaur common in North America in the late Jurassic