/ Dictionary / Index P photosphere: Meaning and Definition of Find definitions for: pho•to•sphere Pronunciation: (fō'tu-sfēr"), [key] — n. a sphere of light or radiance. the luminous visible surface of the sun, being a shallow layer of strongly ionized gases. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: photosphere (Thesaurus) photosensor photo spread Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language