An Ass. Kingswood is famous for the great number of asses kept by the colliers who inhabit that place.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
King’s Plate * King’s Bad BargainNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes