Buckley's chance a forlorn hope; no chance at all. Australian & New Zealand informal
☞ The phrase is often shortened simply to Buckley's. Who or what Buckley was remains uncertain: the name is sometimes said to refer to William Buckley, a convict transported to Australia in 1802 who escaped and lived with the Aborigines for many years, despite dire predictions as to his chances of survival.
1948Vance PalmerGolconda Buckley's chance we have of getting our price if we're left to face the companies alone.