/ Dictionary / Index H heat engine: Meaning and Definition of Find definitions for: heat' en"gine Pronunciation: [key] — Thermodynam. Thermodynam. a mechanical device designed to transform part of the heat entering it into work. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. heated heat equation Related Content Daily Word Quiz: careening Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language