Etymology

Coined by Australian journalist and politician Daniel Deniehy (1828-1865) in 1853 satirising a proposal of William Wentworth for an hereditary peerage in the then colony of New South Wales. (Reference: Bill Wannan, Australian Folklore, Lansdowne Press, 1970, reprint 1979 ISBN 0-7018-1309-1, entry for "Bunyip Aristocracy".)

At that time in the Sydney underworld bunyip was slang for an imposter or con-man, a sense Deniehy may have been taking in, but one almost certainly unknown to Wentworth. (Reference: The Lingo: Listening to Australian English, Graham Seal, University of New South Wales Press, 1999, ISBN 086840-680-5, page 16.)

Noun

1. A peerage (hypothetical or proposed) in Australia. The term is used scornfully for such a scheme.

   1853: we all know the common water mole was transferred into the duck-billed platypus, and in some distant emulation of this degeneration, I suppose we are to be favoured with a "bunyip aristocracy" — Daniel Deniehy, speech at the Victoria Theatre in Pitt St, 15 August 1853, and reported in the Sydney Morning Herald the following day