origin:  Wemba-Wemba language bunyip= "evil spirit" or "devil"
Myth or cryptid? The mystery remains. This creature is also called a "kianpraty". The big foot of the swamp, a creature with various appearances on record, but usually something close to a gorilla mixed with a dog or bear; nocturnal, preys on livestock & humans by lurking at the water's edge like an alligator.
Heavily reported in the past, particularly in Australia, and said to let out a cry before beginning its hunt that scared aborigines away on such nights. Some wonder if it may be a real life creature such as a hippopotamus, walrus, seals, manatee, etc. that was lesser known then and mistaken for some frightening beast. However, that wouldn't account for many reports of it raising on hind legs reaching 10-13 feet.
Interestingly enough, some fossilized bones were found by George Rankin in the Wellington Caves, and it was not any currently known animals. The natives said that the now-labeled Diprodoton -- see image below -- was a "bunyip"; an animal thought to be long extinct, somewhat resembling a rhino or primitive bear (as it's commonly described as hairy). It's been said that the sound aborigines heard was a koala cry, which is what the prehistoric Diprodoton coincidentally resembles.
Bunyip can also mean impostor, or something pretending to be something it isn't -- coined in 1890 by the upper class to describe Australians striving to rise into their aristocracy.
Something that is a forgery or fake, like a "bunyip document".
Looks like a giant koala bear to me.