*backsheesh*

{ ‖ ‖ } n. [ Pers. bakhshīsh, fr. bakhshīdan to give. ] In Egypt and the Turkish empire, a relatively small amount of money given for services rendered (as by a waiter); a gratuity; a “tip”.
Syn. -- gratuity, tip, baksheesh, bakshish, bakshis. [ 1913 Webster + WordNet 1.5 ]