Nyctalopia /(nĭk`tȧ*lō"pĭ*ȧ)/

Nyc·ta·lo·pi·a

Nyctalopia

n.
  1. A disease of the eye, in consequence of which the patient can see well in a faint light or at twilight, but is unable to see during the day or in a strong light; day blindness. (Med.)