One born within sound of Bow-bells, London; one possessing London peculiarities of speech, etc.; one wholly ignorant of country sports, country life, farm animals, plants, and so on.
Camden says the Thames was once called “the Cockney.”
The word has been spelt Cockeney, Cockaneys, Cocknell, etc. “Cocknell” would be a little cock. “Puer in deliciis matris nutritus, ” Anglice, a kokenay, a pampered child. “Niais” means a nestling, as faucon niais, and if this is the last syllable of “Cockney,” it confirms the idea that the word means an enfant gâté.
Wedgwood suggests cocker (to fondle), and says a cockerney or cockney is one pampered by city indulgence, in contradistinction to rustics hardened by outdoor work. (Dutch, kokkeler, to pamper; French, coqueliner, to dangle.)
Chambers in his Journal derives the word from a French poem of the thirteenth century, called The Land of Cocagne, where the houses were made of barley-sugar and cakes, the streets paved with pastry, and the shops supplied goods without requiring money in payment. The French, at a very early period, called the English cocagne men, i.e. bons vivants (beef and pudding men).
“Cry to it, nuncle, as the cockney did to the cels, when she put them into the paste alive.” —Shakespeare: Lear, ii. 4.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894