Where does “澳大拉西亞” come from?

澳大拉西亞 (Chinese) comes from English Australasia, from French Australasie, from Latin australis, from Latin auster, from Proto-Italic *austeros.

Ancestry of “澳大拉西亞”, step by step

Step	Language	Word	Meaning
1	English	Australasia	—
2	French	Australasie	—
3	Latin	australis	southern; Australian; the south pole
4	Latin	auster	The south wind; south
5	Proto-Italic	*austeros	—