Where does “Ostrali” come from?

Ostrali (Balinese) comes from Dutch Australië, from Latin australis, from Latin auster, from Proto-Italic *austeros.

Ancestry of “Ostrali”, step by step

Step	Language	Word	Meaning
1	Dutch	Australië	—
2	Latin	australis	southern; Australian; the south pole
3	Latin	auster	The south wind; south
4	Proto-Italic	*austeros	—