Cockney Rhyming Slang is a specialised form of slang used in the East of London. It is a kind of antilanguage where words are replaced by phrases that rhyme (sound the same): North and south = mouth Adam and Eve = believe Sometimes, the last word is dropped.
Why is Cockney Rhyming Slang called so?
A Cockney is a Londoner; the original definition was someone born near enough to hear the bells of Bow, which meant people in the east of the city. The word Cockney means the egg of a cockerel (male hen) and was meant as an insult, implying dishonesty in business deals by trying to sell non-existent or low quality goods, or so the story goes. The term is now used happily and proudly by the people of the east and north of London, who regard themselves as the 'real' Londoners in a very cosmopolitan city where a lot of the population have come in from other areas of the country or abroad.
As well as having a distinctive pronunciation and many grammatical features, the language of London is most notable for its Rhyming Slang. This consists of using a phrase that rhymes, sounds the same, as the word you want to say, so 'telephone' becomes 'dog and bone'. Unfortunately, many of the phrases then lose the second word, making it very hard for the outsider to guess the original meaning; 'rabbit' for 'talk' comes from the phrase 'rabbit and pork', but few would be able to guess it.
A lot of the original rhyming slang appeared among the market traders in the east end of London in the 19th century, but it is still used and new words and phrases are being invented all the time. At the moment, it is very fashionable to use famous people's names, so the DJ Pete Tong is used meaning 'wrong'- 'thing's have gone Pete Tong'.
Here is The List of Cockney Rhyming Slangs beginning with N.
Nails and tacks: (UK) Nails and tacks = fax
Nanny goat: (UK) Nanny goat = coat
Ned Kelly: (UK) Ned Kelly = telly (television) Ned Kelly was an Australian criminal.
Needle and pin: (UK) Needle and pin = gin
Nelly Duff: (UK) Nelly Duff = puff (breath) 'Not on your Nelly' is used to mean 'Not on your life'.
Nelson Mandela: (UK) Nelson Mandela = Stella Artois, a popular Belgian beer, known as Stella. It is normally called either 'Nelson' or 'Mandela', but the two words are rarely used together: I'd like a pint of Mandela.
Niagara Falls: (UK) Niagara Falls = balls (testicles) Often used as just 'Niagaras'.
Niki Lauder: Niki Lauder = powder (used to mean the drug cocaine) Niki Lauder was a Formula One racing driver.