To save one’s pomp at whist, is to score five before the adversaries are up, or win the game: originally derived from pimp, which is Welsh for five; and should be, I have saved my pimp.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
To Pommel * PompaginisNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes