/ Dictionary / Index P phosphoroscope: Meaning and Definition of Find definitions for: phos•phor•o•scope Pronunciation: (fos-fôr'u-skōp", -for'-), [key] — n. an instrument for measuring the duration of evanescent phosphorescence in different substances. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. phosphoro- phosphorous Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language