/ Dictionary / Index C coherent light: Meaning and Definition of Find definitions for: coher'ent light' Pronunciation: [key] light in which the electromagnetic waves maintain a fixed and predictable phase relationship with each other over a period of time. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. coherent coherer Related Content Daily Word Quiz: reclusive Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language