/ Dictionary / Index C clean energy: Meaning and Definition of Find definitions for: clean' en'ergy Pronunciation: [key] energy, as electricity or nuclear power, that does not pollute the atmosphere when used, as opposed to coal and oil, that do. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. clean-cut cleaner Related Content Daily Word Quiz: blithesome Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language