/ Dictionary / Index I immersion heater: Meaning and Definition of Find definitions for: immer'sion heat"er Pronunciation: [key] a small electric coil used to heat a liquid, as a cup of water, in which it is immersed. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. immersion foot immersionism Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language