capibara vs gnawer

capibara and gnawer both are nouns.

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

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

capibara: pig-sized tailless South American amphibious rodent with partly webbed feet; largest living rodent
gnawer: relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing

Other hypernyms of capibara include rodent.

capibara (noun)	gnawer (noun)
pig-sized tailless South American amphibious rodent with partly webbed feet; largest living rodent	relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing