Green’s Dictionary of Slang

soldiers bold adj.

(Aus./N.Z.) cold.

1952		Argus (Melbourne) 13 June 4s/1: If the squatter’s daughter’s cast iron pot, I’ll have a fairy bower, but if it’s soldier’s bold I’ll have a lemon squash.
1967		‘Whisper All Aussie Dict.’ in Kings Cross Whisper (Sydney) xl 4/4: soldiers: Cold, from soldiers bold.
1972		Dodson & Saczek Dict. of Cockney Rhy. Sl.
1999		G. Seal Lingo 91: soldier’s bold is cold, usually just soldiers.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 172/2: soldiers bold n. 2 cold.