/ Dictionary / Index P photocathode: Meaning and Definition of Find definitions for: pho•to•cath•ode Pronunciation: (fō"tō-kath'ōd), [key] — n. a cathode, typically of a cesium or sodium compound, having the property of emitting electrons when activated by light or other radiation. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: photocathode (Thesaurus) photocatalysis photocell Related Content Daily Word Quiz: endear Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language