Green’s Dictionary of Slang

(Aus.) euph. for bugger n.¹ ; thus in pl., generic for obscene language.

1895		Mirror of Life 12 Jan. 14/1: ‘I can’t get near enough to the blanker,’ exclaimed Tom.
1895		Mirror of Life 8 June 9/3: Surely it was not our old friend Dicky who was up before the stewards [...] for using ‘blankers’ to one of the devout occupants of the members’ enclosure. Unfortunately, Dicky, everybody is not like your clerk who, in consideration of his big salary, puts the ‘unparliamentary’ out with his washing.
1901		Bulletin (Sydney) 13 July 32/2: De la Ray [...] is a fair blanker. If his crowd catch a bushman, they cut his throat.
1904		Sun. Times (Perth) 6 Nov. 6 Nov. 4/6: No blasted tribe of mangy skip two and carry one blankers are goin’ ter circumsize me!
1903		Bulletin (Sydney) 3 Dec. 16/1: Have another, you blank blanker, Jim!
1907		N.Z. Truth 21 Dec. 7/4: Somebody used horrible language to him [...] and Bob repeated it by saying, ‘What? Call me a blankety blank blanking blanker!!’.
1912		Bulletin (Sydney) 8 Aug. 15/2: You lot of blankers, I’ll say; a nice lot o’ (variegated) cows yous are to scoff at a (something) cove as is saved. If yous don’t like it yous can blanky well go to blanky —.
1915		T. Burke Nights in Town 304: Turn the blanker over!
1919		C.H. Thorp Handful of Ausseys 199: Yer wayback, silly blanker [...] that bloke’s wax.
1923		Sun. Times (Perth) 11 Feb. 1s/4: [headline] The Blanker Who Wouldn’t Drink.