coypu vs gnawer

coypu and gnawer both are nouns.

Word	Noun	Adjective	Verb	Adverb
coypu	Yes	No	No	No
gnawer	Yes	No	No	No

As nouns, gnawer is a hypernym of coypu; that is, gnawer is a word with a broader meaning than coypu:

coypu: aquatic South American rodent resembling a small beaver; bred for its fur
gnawer: relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing

Other hypernyms of coypu include rodent.

coypu (noun)	gnawer (noun)
aquatic South American rodent resembling a small beaver; bred for its fur	relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing