/ Dictionary / Index P photosensor: Meaning and Definition of Find definitions for: pho•to•sen•sor Pronunciation: (fō'tu-sen"sur, -sôr), [key] — n. a photocell used to detect light. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. photosensitize photosphere Related Content Daily Word Quiz: feline Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language