Cockney

From Grose's Dictionary of the Vulgar Tongue (1811):

COCKNEY: A nick name given to the citizens of London, or persons born within the sound of Bow bell, derived from the following story: A citizen of London, being in the country, and hearing a horse neigh, exclaimed, Lord! how that horse laughs! A by-stander telling him that noise was called NEIGHING, the next morning, when the cock crowed, the citizen to shew he had not forgot what was told him, cried out, Do you hear how the COCK NEIGHS? The king of the cockneys is mentioned among the regulations for the sports and shows formerly held in the Middle Temple on Childermas Day, where he had his officers, a marshal, constable, butler, &c. See DUGDALE'S ORIGINES JURIDICIALES, p. 247.—Ray says, the interpretation of the word Cockney, is, a young person coaxed or conquered, made wanton; or a nestle cock, delicately bred and brought up, so as, when arrived a man's estate, to be unable to bear the least hardship. Whatever may be the origin of this appellation, we learn from the following verses, attributed to Hugh Bigot, Earl of Norfolk, that it was in use, in the time of king Henry II:

Was I in my castle at Bungay,
Fast by the river Waveney,
I would not care for the king of Cockney; [i.e. the king of London].

I don't believe a word of it, of course; and neither do you.  You might as well say:  'a visitor from London, eating for the first time that country delicacy called cooked bullock's knees, did praise the dish so loudly the locals began calling him the COOKED-KNEE MAN, whence derived &c. &c.'