Ordained. To be japanned; to enter into holy orders, to become a clergyman, to put on the black cloth: from the colour of the japan ware, which is black.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Janizaries * JarkNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes