the quantity of heat required to raise the temperature of 1g of water by 1°C under standard conditions, equal to 4.1868 joules. Also called small calorie

the amount of heat required to raise the temperature of 1kg of water by 1°C under standard conditions. Also called kilocalorie, large calorie

a unit equivalent to the kilocalorie expressing the energy-producing value of food when used in the body

an amount of food that has an energy-producing value of one kilocalorie