rock rabbit vs pika

rock rabbit and pika both are nouns.

Word	Noun	Adjective	Verb	Adverb
rock rabbit	Yes	No	No	No
pika	Yes	No	No	No

As nouns, rock rabbit and pika are synonyms defined as:

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

Other synonyms of rock rabbit include coney, cony, mouse hare.

rock rabbit (noun)	pika (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