Definitions by A. Discipulus.
pony up
Meaning: to put (something) up, often money. Pony, derived from pone, Lat. (present imperative, sing.) Poneo, ponere, "to put" Hence, to pony up is frequently used in monetary settings and games of chance where the demand is made to "pony up", or stake a monetary sum.
pony up by A. Discipulus. September 3, 2013