Green’s Dictionary of Slang

popular mis-sp. of whatshisname n.

1990		T. Pratchett Eric (2002) 56: ‘If you try and knock me off, demon, you can wossname your ear goodbye.’ [...] ‘Why do you keep saying wossname?’ said Rincewind. ‘Limited wossname. Doodah.’.
1998		Guardian Sport 18 Sept. 16: It’ll give them wossnames, them Neville Brothers, a run for their bleedin’ money.
2001		K. Waterhouse Soho 153: Then they handed him over to the wossname, council environmental health service.