A goose. CANT. Saint Tibb’s evening; the evening of the last day, or day of judgment: he will pay you on St. Tibb’s eve. Irish.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Tibby * TickNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes