cavy vs rodent

cavy and rodent both are nouns.

Word	Noun	Adjective	Verb	Adverb
cavy	Yes	No	No	No
rodent	Yes	No	No	No

As nouns, rodent is a hypernym of cavy; that is, rodent is a word with a broader meaning than cavy:

cavy: short-tailed rough-haired South American rodent
rodent: relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing

Other hypernyms of cavy include gnawer.

cavy (noun)	rodent (noun)
short-tailed rough-haired South American rodent	relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing