The first woman seen by a man, or man seen by a woman, on St. Valentine’s day, the 14th of February, when it is said every bird chuses his mate for the ensuing year.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Vain-glorious * To VampNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes