Green’s Dictionary of Slang

(Aus.) a prank, a practical joke.

1862		‘Artemus Ward’ Artemus Ward, His Book 79: Extry charg fur this larst remark. It’s a goak.
1866		Sportsman 4 Sept. 2/1: Notes on News [...] N.B. As Artemus Ward might phrase it, this is intended for a ‘goak’.
1869		Bell’s Life in Sydney 22 May 13/2: Curious name that, I think Mr Good is a good height. See the goak.
1871		Waterford Standard 29 Mar. 4/3: The afair has caused some amusement to lovers of a good ‘goak’.
1880		Bulletin (Sydney) 20 Mar. 5/3: [T]hose concerned in the management of the institution were complimented upon the success which had attended their efforts. Surely this is a ‘goak.’.
1882		Bristol Magpie 10 Aug. 3/1: (N.B.—This reads like a ‘goak,’ but it isn’t one).
1881		Bulletin (Sydney) 5 Feb. 9/1: Now where’s the ‘goak,’ or rather, where’s the girl, and what was she so deuced particular over?
1895		Riverina Recorder (Balranald, NSW) 16 Jan. 2/5: Some people cannot take a ‘goak’.
1900		Sporting Times 24 Feb. 2/5: The enclosed ‘goak’ may find a place to fill up some odd corner: — Military Sports at Sterkstrooms.
1931		N.T. Times (Darwin) 9 Jan. 8/1: Aussie can be best described in the words of Joh Billings: ‘This is a “goak”.’ [AND].