Pony Up Meaning

(transitive, idiomatic) To pay (usually a bill, debt or due).

Example: 2009 January 25, Frank Rich, “No Time for Poetry”[1], New York Times:
  Only then did we learn that he doled out billions in secret, last-minute bonuses to his staff last month, just before Bank of America took over and just before the government ponied up a second bailout to cover Merrill’s unexpected $15 billion fourth-quarter loss.
September, 1824, The Atlantic magazine, p. 343:
  Every man, save Silvy, vociferously swore that he had ponied up his "quarter:" whereupon the landlady observed that Silvy the less had not paid his reckoning.