Noun
(Australia, New Zealand)
An informal gossip network, especially in a rural area such as the outback; also, a component in the network (either a person or an imagined wire).
Synonyms: bush telegraph, grapevine, jungle telegraph
A message or story transmitted through such an informal network, especially one containing false information.
Synonym: mulga
(Australia, historical) A system for long-distance communication used by Aboriginal Australians, chiefly using smoke signals; also, a message or signal sent using such a system.
Source: en.wiktionary.org