CON. MONEY. Damages directed by a jury to be paid by a convicted adulterer to the injured husband, for criminal conversation with his wife.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Cribbeys * CrimpNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes