calorie
noun
°a non-SI unit of energy, equivalent to approximately 4.2 joules. This unit was widely used in chemistry and physics, being the amount of heat needed to raise the temperature of 1 gram of water by 1°C.
°the kilocalorie, kilogram calorie or large calorie. A unit of energy 1,000 times larger than the normal calorie. It is equivalent to approximately 4.2 kilojoules.