This is the 7478th most frequent Catalan word.
australiana
Australian (female).
Here, 'australiana' is used as a noun to refer to a female person from Australia.
L'australiana ve de Melbourne.
The Australian woman comes from Melbourne.
In this context, 'australiana' is used as an adjective to describe the origin or style of the jacket.
Vaig comprar una jaqueta australiana.
I bought an Australian jacket.
Here, 'australiana' serves as an adjective modifying 'accent' to specify its type or association.