1Any of various rodents of the family Muridae inhabiting rocky areas; specifically †(a) = rock mouse (obsolete); (b) any of several Australian thick-tailed rats constituting the genus Zyzomys; (c) any of several African bush rats constituting the genus Aethomys (also called rock mouse).

2Any of several rat-like rodents of other families inhabiting rocky areas; specifically (a) the dassie rat, Petromus typicus (family Petromuridae), of southern Africa; (b) either of two burrowing South American rodents constituting the genus Aconaemys (family Octodontidae).