The definition of a calorie is a measure of energy in food, specifically the measure of heat needed to raise a kilogram or a gram of water by one degree Celsius.(noun)
See calorie in Webster's New World College Dictionary
Origin: Fr < L calor, heat; akin to calere, to be warm < IE base *kel-, warm > OE hlēowe, warm
See calorie in American Heritage Dictionary 4
Origin: , from Latin calor, heat; see caloric.
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