sweetener

/ˈswiːtənər/ noun [C]

Definition

› something that is given to someone in order to make an offer or situation more attractive and acceptable: a $50m/cash, etc. sweetener The government is to offer a £50m sweetener to persuade workers at state-owned factories facing closure to take new jobs with private companies. Flexible benefits packages, including extra holiday entitlement, have been offered to employees as a sweetener.

(Definition of sweetener noun from the Cambridge Business English Dictionary © Cambridge University Press)