First, there's ghingi, or more properly the ghingi-ghingi, the sound made by a monster or demon or god that can apparently be mimicked by a clever Outbacker through a device rather like a bull-roarer. (p. 84-85)
Next, there's Wangul, the name for the great Dweller in the Waters, apparently another god/beast/monster. Like the Bunyip, this seems to be something greatly feared rather than sought out. (p. 246/247)
Also, there's Babba, or "water", which gets repeated over and over during what's meant to be a comic scene when they capture a native and torture him a little to get him to lead them to his tribe's hidden water supply. (p. 260-263)
Last of all, there's the term Bilya Bakan, meaning 'sorcerer', applied by an advanced tribe to one of the captured explorers who they've become convinced has magical powers. Shaman or witch doctor wd probably also be rough equivalents in other cultures. (p. 346/347).
In addition to these, there are two brief descriptions of what Aborigine language sounded like to the English interlopers:
[a native] "addressed Mackay in a series of unintelligible ejaculations -- presumably of inquiry" (p. 334)
"the aged chief suddenly hastened forward, and shrilled a few words to Bentley, which had the effect of arousing that happy man to a true sense of his responsibilities. He answered the old warrior in an odd monosyllabic language, which he spoke with perfect ease, much to the astonishment of the youthful members of the group, who had never before heard a white man converse so fluently in the savage tongue. For some moments they held high conversation thus . . . " (p. 345)
Of course, I don't believe for a moment that there's such a thing as a single Aborigine language spoken all over the continent, any more than there's a 'Native American' tongue or a language known as 'European' or 'Asian'. But a few universals for words like 'water' don't push probability too badly, even after over 40,000 years of divergence. I'd hoped when reading this to catch some hints of the origins of Ghan-buri-Ghan, but if anything I'd afraid they're more like THE HOBBIT's goblins. Alas. Would that it were not so.
current reading: CROW PLANET