(CAMBRIDGE) To sup at one’s own expence. If a MAN asks you to SUP, he treats you; if to SIZE, you pay for what you eat—liquors ONLY being provided by the inviter.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Size of Ale * SizarNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes