corythosaurus vs corythosaur

corythosaurus and corythosaur both are nouns.

Word	Noun	Adjective	Verb	Adverb
corythosaurus	Yes	No	No	No
corythosaur	Yes	No	No	No

As nouns, corythosaurus and corythosaur are synonyms defined as:

corythosaurus and corythosaur: duck-billed dinosaur with nasal passages that expand into a crest like a hollow helmet

corythosaurus (noun)	corythosaur (noun)
duck-billed dinosaur with nasal passages that expand into a crest like a hollow helmet	duck-billed dinosaur with nasal passages that expand into a crest like a hollow helmet