| Noun | 1. | heat energy - a form of energy that is transferred by a difference in temperatureenergy, free energy - (physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs; "energy can take a wide variety of forms" geothermal energy - energy derived from the heat in the interior of the earth heat of dissociation - the heat required for a fluid substance to break up into simpler constituents heat of formation - the heat evolved or absorbed during the formation of one mole of a substance from its component elements heat of solution - the heat evolved or absorbed when one mole of a substance is dissolved in a large volume of a solvent heat of transformation, latent heat - heat absorbed or radiated during a change of phase at a constant temperature and pressure specific heat - the heat required to raise the temperature of one gram of a substance one degree centigrade |