baksheesh

British subjects traveling abroad in the 17th century likely picked up baksheesh in Asia, where they would have heard the term used to mean "gratuity, a present of money, tip"—a meaning they directly adopted. Etymologically speaking, baksheesh is from Persian bakhshīsh, which is also the source of the word buckshee, meaning "something extra obtained free," "extra rations," or "windfall, gratuity." Buckshee never made it across the pond to the U.S., and is strictly used in British English.