Green’s Dictionary of Slang

(Aus. / N.Z.) to seduce, to go off with a woman in the hope of achieving seduction.

1907		Sun. Times (Perth) 10 Feb. 4/8: New York cables announces that ‘a man named George Witzhoff has been arrested for marrying and deserting 100 woman in various pacts of the U.S.A.’ As this paper’s tame saur-kraut interpreter pronounces ‘Witzhoff’ as ‘Wizz-off’ he seems to have acted up to his cognomen.
1960		J. Walker No Sunlight Singing (1966) 195: I never lumbered none. I never tried, but I see blokes whizzin ’em off.
1972		A. Chipper Aussie Swearers Guide 48: Race off: Compare brit. knock off, having it off with, etc .
1977		(con. 1941) R. Beilby Gunner 308: Good on ya, Digger! Whizz ’er off while she’s hot.
1986		C. Bowles G’DAY 14: SHANE: Just some blonde tart I conned up at Selina's. Top sort. [...] all over me like a rash, she was. [...] Raced me off soon as we got in the door. Oastie with Qantas. Rooted er silly all night.
1996		(con. 1964-65) B. Thorpe Sex and Thugs and Rock ’n’ Roll 86: ‘I’ll flatten the first bitch that tries to race you off’.
2003		McGill Reed Dict. of N.Z. Sl. 168: race off To seduce. ANZ 1960s.