gratuity vs backsheesh

gratuity and backsheesh both are nouns.

Word	Noun	Adjective	Verb	Adverb
gratuity	Yes	No	No	No
backsheesh	Yes	No	No	No

As nouns, gratuity and backsheesh are synonyms defined as:

gratuity and backsheesh: a relatively small amount of money given for services rendered (as by a waiter)

Other synonyms of gratuity include baksheesh, bakshis, bakshish, pourboire, tip.

gratuity (noun)	backsheesh (noun)
a relatively small amount of money given for services rendered (as by a waiter)	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