gratuity (plural gratuities)
- An additional payment given freely as thanks for service &c.
- Euphemistic form of fee, in contexts where such additional payments have been made obligatory.
- Euphemistic form of bribe.
- (additional payment offered in thanks): douceur, grace, tip; baksheesh (Turkish and Middle Eastern contexts); cumshaw (SE Chinese contexts; archaic); see also gift
- (obligatory fee): service charge; douceur, tip (euphemistic)
- (bribe): Wikisaurus:bribe
reward provided freely, without obligation