Definitions
1.AdjectiveNeat, smartly dressed, attractive.
2.NounAttractiveness or charm in dress, appearance, or manner."Without a diploma, he relies on spiff alone to climb the corporate ladder."
3.NounA well-dressed man; a swell.
4.NounA bonus or other remuneration, given for reaching a sales goal or promoting the goods of a particular manufacturer. Originally from textile retailing, a percentage given for selling off surplus or out-of-fashion stock, of which the sales person could offer part as a discount to a customer.
5.NounAlternative form of spliff (“hand-rolled marijuana cigarette”).
6.Verb(usually with up or out) To make spiffy (attractive, polished, or up-to-date)
7.VerbTo reward (a salesperson) with a spiff or bonus.
8.VerbTo attach a spiff or bonus to the selling of (a product)