/ Dictionary / Index P photolysis: Meaning and Definition of Find definitions for: pho•tol•y•sis Pronunciation: (fō-tol'u-sis), [key] — n. the chemical decomposition of materials under the influence of light. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. photoluminescence photolyze Related Content Daily Word Quiz: effervescent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language