A military term for small beer, five pints of which, by an act of parliament, a landlord was formerly obliged to give to each soldier gratis.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Acorn * ActeonNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes