noun, plural wal·la·bies ( especially collectively ) wal·la·by.
any of various small and medium-sized kangaroos of the genera Macropus, Thylogale, Petrogale, etc., some of which are no larger than rabbits: several species are endangered.
any of various herbivorous marsupials of the genera Lagorchestes (hare wallabies), Petrogale (rock wallabies), Protemnodon, etc, of Australia and New Guinea, similar to but smaller than kangaroos: family Macropodidae
2.
slang (Austral) on the wallaby, on the wallaby track (of a person) wandering about looking for work