A piece of sport practised at wakes, horse-races, and fairs in Leicestershire: a cock being tied or fastened into a hat or basket, half a dozen carters blindfolded, and armed with their cart whips, are placed round it, who, after being turned thrice about, begin to whip the cock, which if any one strikes so as to make it cry out, it becomes his property; the joke is, that instead of whipping the cock they flog each other heartily.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Whinyard * Whip JacksNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes