Pronunciation: (thûr"mō-dī-nam'iks), [key]
—n. (used with a sing. v.)
the science concerned with the relations between heat and mechanical energy or work, and the conversion of one into the other: modern thermodynamics deals with the properties of systems for the description of which temperature is a necessary coordinate.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.