To bang someones back passage with either a penis , cucumber or rolling pin!
Hmmm Smash your back doors in - Do we really need an example?? I have pictures if that would be more useful?
by Steffithebackdoorsmasher June 17, 2011
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A term used to describe the act of anal sex, popularised by Keith Lemon.
(courtesy of Keith Lemon),

'I want to smash your back door in and spunk on your tits'.
by sphilli2004 February 14, 2011
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