Green’s Dictionary of Slang

stoom out v.

[shtoom adj.]

(Aus.) to render someone silent; thus to kill.

[Aus]E.S. Sorenson Quinton’s Rouseabout and other Stories 119: Seemed plain ter me as Garron ’ad left ’is team at the station an’ rode ’ome; ’as a kick-up with the ole gerl over something – God knows wot – an’ she stooms him out – accidental, as yer might say. Then she hits on the black stump as an orlright place ter ’ide im, [...] so she’d easy enough lug ’im up there an’ drop ’im in.