Source : Webster's Revised Unabridged Dictionary (1913)

Phosphene \Phos"phene\, n. [Gr. ? light + ? to show.] (Physiol.)
   A luminous impression produced through excitation of the
   retina by some cause other than the impingement upon it of
   rays of light, as by pressure upon the eyeball when the lids
   are closed. Cf. {After-image}.