pony

noun pl. ponies

a small horse of any of a number of breeds, usually not over 58 inches high at the withers
1. something small of its kind
2. ☆ a small liqueur glass or the amount it will hold
☆ Informal a literal translation of a work in a foreign language, used in doing schoolwork, often dishonestly; crib
☆ Slang a racehorse
Brit., Slang the sum of twenty-five pounds

transitive verb, intransitive verb ponied, ponying

Slang to pay (money), as to settle an account: with up

See pony in American Heritage Dictionary 4