hamster vs rodent

hamster and rodent both are nouns.

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

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

hamster: short-tailed Old World burrowing rodent with large cheek pouches
rodent: relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing

Other hypernyms of hamster include gnawer.

hamster (noun)	rodent (noun)
short-tailed Old World burrowing rodent with large cheek pouches	relatively small placental mammals having a single pair of constantly growing incisor teeth specialized for gnawing