Green’s Dictionary of Slang

(Aus.) a euph. for bloody adj. (1)

1968

R.D. Magoffin We Bushies 62: I see you’ve got the jilly knack / Of drafting several ways. [Ibid.] 64: You’ll put the sheep on conveyer belts / And whizz them to the shed, / There’ll be no jilly shearers, / There’ll be a chemist there instead. [Ibid.] 71: Y’shanghaied me Feyers y’jilly rat!