Source : Webster's Revised Unabridged Dictionary (1913)

Hemeralopia \Hem`e*ra*lo"pi*a\, n. [NL., fr. Gr. ?, the opposite
   of ?; ? day + ? of ?. See {Nyctalopia}.] (Med.)
   A disease of the eyes, in consequence of which a person can
   see clearly or without pain only by daylight or a strong
   artificial light; day sight.

   Note: Some writers (as Quain) use the word in the opposite
         sense, i. e., day blindness. See {Nyctalopia}.

Source : WordNet®

hemeralopia
     n : inability to see clearly in bright light [syn: {day
         blindness}]