Misnaming and misapplying any hard word; from the character of Mrs. Slipslop, in Fielding’s Joseph Andrews.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Slipslops * SlopNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes