Source : Webster's Revised Unabridged Dictionary (1913)

Calorific \Cal`o*rif"ic\, a. [L. calorificus; calor heat +
   facere to make; cf. F. calorifique.]
   Possessing the quality of producing heat; heating.

   {Calorific rays}, the invisible, heating rays which emanate
      from the sun, and from burning and heated bodies.

Source : WordNet®

calorific
     adj : heat-generating; "the calorific properties of fuels"