something given or paid over and above what is due.

a sum of money granted or given to an employee, a returned soldier, etc., in addition to regular pay, usually in appreciation for work done, length of service, accumulated favors, etc.

something free, as an extra dividend, given by a corporation to a purchaser of its securities.

a premium paid for a loan, contract, etc.

something extra or additional given freely

Every purchaser of a pound of coffee received a box of cookies as a bonus.

noun

additional compensation , benefit , bounty , commission , dividend , fringe benefit , frosting * , gift , golden parachute , goody * , gratuity , gravy * , hand-out , honorarium , ice * , perk * , plus * , premium , prize , reward , special compensation , tip , allowance , award , boon , bribe , compensation , gravy , perk , signing , subsidy