Green’s Dictionary of Slang

(Aus. ex-soldiers) the First World War.

1929		Canberra Times 17 Apr. 8/7: He wanted a word like that for the big stoush (the Great War).
1941		Baker Popular Dict. Aus. Sl. 9: big snarl The 1914–18 War. Diggers’ slang.
1945		Baker Aus. Lang. 120: For a considerable period that war was known as the Big Stoush, until a bigger Stoush came along in 1939 to force it out of currency.
1952		A.W. Upfield New Shoe 124: Been cobbers since kids and wanted to keep together in the Great Stoush.
1955		N. Pulliam I Travelled a Lonely Land (1957) 240/1: stoush-up – a brawl. stoushed up Big Stoush – World War I.
1963		A.E. Farrell Vengeance 23: A broad leather belt [...] bearing the inscription – Gott Mit Uns, Billy’s souvenir of the ‘Big Stoush’ of 1914–18.
1973		R. Park The Companion Guide to Sydney 24: The Big Stoush, the war of 1914-18.
1989		J. Hughes Aus. Words and their Origins 550: The Big Stoush, the war of 1914-18.
2005		posting at Go-Betweens Message Board 25 May 🌐 The term [i.e. stoush] derived from the British dialect ‘stashie’, ‘stushie’, meaning ‘an uproar, disturbance, quarrel’. It was adapted to apply to ‘a war’. In particular, World War I was known as ‘The Big Stoush’.
2006		A. Pilkington Four of Diamonds 54: I cut timber down there for a couple of years after the Big Stoush.