Source : Webster's Revised Unabridged Dictionary (1913)

Photopsia \Pho*top"si*a\, n. [NL., fr. Gr. fw^s, fwto`s, light +
   ? sight.] (Med.)
   An affection of the eye, in which the patient perceives
   luminous rays, flashes, coruscations, etc. See {phosphene}.