WordNet (r) 3.0 (2006):

kilocalorie
    n 1: a unit of heat equal to the amount of heat required to
         raise the temperature of one kilogram of water by one
         degree at one atmosphere pressure; used by nutritionists to
         characterize the energy-producing potential in food [syn:
         Calorie, kilogram calorie, kilocalorie, large
         calorie, nutritionist's calorie]