pony

Concise Oxford English Dictionary © 2008 Oxford University Press:
pony/ˈpəʊni/

▶noun (pl. ponies)

• 1 a horse of a small breed, especially one below 15 hands (or 14 hands 2 inches).

  ■ (the ponies) informal, chiefly N. Amer. racehorses.

• 2 informal a small glass or measure of alcoholic drink.

• 3 Brit. informal twenty-five pounds sterling.

▶verb (pony something up) N. Amer. informal hand over a sum of money, especially to settle an account.

– origin C17: prob. from Fr. poulenet ‘small foal’.