Definition from Wiktionary, the free dictionary
- IPA: /ˈkæləri/
- (physics and chemistry, obsolete) the gram calorie or small calorie, 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 energy needed to raise the temperature of 1 gram of water by 1 °C.
- (nutrition) kilogram calorie or large calorie. A unit of energy 1000 times larger than the gram calorie. It is equivalent to the gram kilocalorie, approximately 4.2 kilojoules.
Usage notes 
- Most scientific studies are now carried out using the joule (an SI unit).
- In nutritional contexts the term calorie refers to the kilogram calorie and the term kilocalorie refers to 1000 gram calories. Thus the two terms are equivalent.
- European legislation now requires foods to be labelled with the term kilocalorie.
Derived terms 
- 4° calorie
- 15° calorie
- 20° calorie
- calorific value
- caloric (US)
- calorific (British)
- gram calorie
- kilogram calorie
- mean calorie
amount of heat to raise 1 gram of water by 1°C
calorie f (plural calories)
- Plural form of caloria