rock rabbit vs mouse hare

rock rabbit and mouse hare both are nouns.

Word	Noun	Adjective	Verb	Adverb
rock rabbit	Yes	No	No	No
mouse hare	Yes	No	No	No

As nouns, rock rabbit and mouse hare are synonyms defined as:

rock rabbit and mouse hare: small short-eared burrowing mammal of rocky uplands of Asia and western North America

Other synonyms of rock rabbit include coney, cony, pika.

rock rabbit (noun)	mouse hare (noun)
small short-eared burrowing mammal of rocky uplands of Asia and western North America	small short-eared burrowing mammal of rocky uplands of Asia and western North America
hyrax that lives in rocky areas