› COMMUNICATIONS a part of a newspaper, report, etc. that is published in addition to the main part: In this supplement we look at how companies can measure their carbon footprint. a Sunday/monthly/quarterly supplement
› a medicine that contains substances that you need to stay healthy in addition to what you get in your food: dietary/nutritional/food supplements
› MARKETING an additional amount that you pay for a particular service, a better place to stay, etc.: a supplement of sth We paid a supplement of €40 for a room with a balcony.
› HR, WORKPLACE an amount that you earn in addition to your basic salary: The income from the investments supports universities by paying for scholarships and salary supplements.
› something that is done as an addition to an activity or process in order to improve it: a supplement to sth The measures were introduced as a supplement to the state's disaster plan.