/ Dictionary / Index W water heater: Meaning and Definition of Find definitions for: wa'ter heat"er Pronunciation: [key] a household appliance consisting of a gas or electric heating unit under a tank in which water is heated and stored. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. waterhead water hemlock Related Content Daily Word Quiz: denizen Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language