Green’s Dictionary of Slang

inside n.1

(Aus.) central Australia; also as adj. or adv.

[R. Henning letter in Merrit & O’Brien Striding Years (1985) 80: When Biddulph first took up Exmoor it was a very outside run north ].
[Aus]C.E.W. Bean On the Wool Track 27: Whilst the ‘inside’ stations may grow [sheep] for meat if they care, the ‘outside’ stations grow for wool.
[UK]E. Hill Territory 444: Inside: The cities and colonized places.
[Aus]Bulletin 20 Jan. 11: Some young, back-country shearers ‘inside’ for the first time reckon wide-open Yass the Paris of the south.
[Aus]Sydney Morning Herald 20 Oct. Colour Mag. 24: The Charnleys think they have been out west long enough and next year they will take their two children ‘down inside’, somewhere east of Bourke [GAW4].

In derivatives

insider (n.)

(Aus.) person who lives in central Australia.

[UK]Partridge DSUE (8th edn) 598/2: late C.19–20.