/ Dictionary / Index P photoisomerization: Meaning and Definition of Find definitions for: pho•to•i•som•er•i•za•tion Pronunciation: (fō"tō-ī-som"ur-u-zā'shun), [key] — n. Chem. isomerization induced by light. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. photoionization photojournalism Related Content Daily Word Quiz: opulent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language