/ Dictionary / Index H heat exchanger: Meaning and Definition of Find definitions for: heat' exchang"er Pronunciation: [key] a device for transferring the heat of one substance to another, as from the exhaust gases to the incoming air in a regenerative furnace. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. heater heat exhaustion 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