n.
the scientific name for a Rock-Wallaby (q.v.). The name was given by J. E. Gray,in the `Magazine of Natural History' (vol. i. p. 583), 1837.(Grk. petra, rock, and galae, a weasel.)
·noun Any Australian kangaroo of the genus Petrogale, as the rock wallaby (P. penicillata). ...
Webster's Dictionary of the English Language