Literally, a person born within earshot of the bells of St Mary-le-Bow church in what is now the City of London. However, technically speaking there can be no cockneys born after 1945 since the bells were destroyed by German bombs during WWII.

Today the term has expanded to encompass not only those from East London specifically but from London in general. The latter tends to be attributed by non-Londoners, stemming from their ignorance of the true meaning of the word.
by hux June 1, 2003
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Person from the East End of London. Supposedly 'born with the sound of bow-bells'. When I used to live in Houghton Regis there were some next door, and they talked and acted nothing like the ones in Eastenders (most of whom are posh actors trying to sound working class). And let's be honest, a lot of TV producers are lovies and darlings who seem to think working class people (especially cockneys) are automatically criminals. Alright, I'm sure there are criminals in the East End. But thanks to a succession of useless, soft-head, corrupt UK governments, there are bloody villains everywhere you go in Britain. Counties around the south of England tend of be full of 'mockneys' - total arseholes who think putting on a fake cockney accent makes them sound hard (but don't tell their mummies).
Mo Slater has stolen a baby's cot and is now selling it like the heartless criminal she is. Egads! You nasty evil cockney!

Oh, go smell the coffee, BBC.
by StormSworder August 12, 2006
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person from london's east end.
rhyming slang used in london's east end
eg: mate = china plate = china
and so mate = china
by bru January 30, 2004
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Someone born within the sound of Bow Bells in London.
by chump April 23, 2003
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According to a 2003 NCIS report

75% of the 300 most wanted men in the UK were 'white middle aged men from the south east' in other words cockney gangsters or the 'English Mafia'
by bigmeuprudeboy September 12, 2003
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Noble upstanding citizens of East London, NOT South, NOT West, and definitely NOT North Londoners, they're all a bunch of arseholes. So get it right you Northern Monkeys, Cockneys are from East London. Now get on and dig for coal or whatever it is you lot do for a living (walk to the dole office more than likely).
Cockneys = The best people in England.
by Peldon March 15, 2004
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