Tip or payment for services above the cost of the product or service. See also service charge. The passenger's personal expression of thanks, tips, to the ship's service personnel for services received.
Gift for service rendered.
a relatively small amount of money given for services rendered (as by a waiter)
an award (as for meritorious service) given without claim or obligation
a gift given without regard for return
Gift, usually money, given in return for service.
A voluntary payment for services rendered above the amount due on the guest check. Usually, the accepted proper gratuity is a monetary amount equal to 15% of the total amount due of the guest check.