Wallaby n. : Any one of numerous species of kangaroos belonging to the genus Halmaturus, native of Australia and Tasmania, especially the smaller species, as the brush kangaroo (H. Bennettii) and the pademelon (H. thetidis). The wallabies chiefly inhabit the wooded district and bushy plains.

Example:
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Taxonomy
Wallaby, population, species, tail wallabies, Suborder, free encyclopedia, macropod, Macropus rufogriseus, joey, Feral populations, kangaroos, breeding, colony, island, Macropus agilis, Lagostrophus fasciatus, Petrogale penicillata, five species.

Defination from the web:
wallaby is any of about thirty species of macropod (Family Macropodidae) ... Red-necked Wallaby (Macropus rufogriseus) joey in pouch ... A number of wallaby breeding colonies in other parts of the world have been established at times in the past, but only one proved viable. ...