Green’s Dictionary of Slang

arsey adj.1

also arsie, arsy
[tin-arsed adj.]

(Aus.) lucky; occas. as n., a lucky person.

[Aus]J. Walker No Sunlight Singing (1966) 23: I was real arsy to pick up a job here.
[Aus]S. Gore Holy Smoke 30: He’d have to be pretty arsey, wouldn’t he? Seein’ he’s a Jew, and it’s them Philistine bludgers that draw it!
[Aus](con. 1941) R. Beilby Gunner 87: Now you just lie back an’ take it easy. Ya got a homer, mate, you arsey bastard.
[Aus]T. Davies More Aus. Nicknames 25: Arsie Is very lucky at cards.
[Aus]R. Aven-Bray Ridgey-Didge Oz Jack Lang 17: Arsey Lucky.
[Aus]C. Bowles G’DAY 76: You arsey bastard. Yer gunna be quids in.
[Aus]R.G. Barrett Boys from Binjiwunyawunya 156: A dubbo like you would be arsey enough to fluke something like this.
[Aus]B. Moore Lex. of Cadet Lang. 16: arsy [...] lucky.
[UK]Observer Screen 5 Mar. 9: Grassy knoll? My arsey knoll, more like!
[Aus]N. Cummins Tales of the Honey Badger [ebook] [I]t was yours truly who grabbed the chese and planted it. Very arsey!