The Collaborative International Dictionary of English v.0.48:

Blindness \Blind"ness\, n.
   State or condition of being blind, literally or figuratively.
   --Darwin.
   [1913 Webster]

   Color blindness, inability to distinguish certain color.
      See Daltonism.
      [1913 Webster]

WordNet (r) 3.0 (2006):

blindness
    n 1: the state of being blind or lacking sight [syn:
         blindness, sightlessness, cecity]

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "blindness":
   albinism, astigmatism, astigmia, bad eyesight, blurred vision,
   deafness, defect of vision, dim-sightedness, dogmatism,
   double sight, double vision, faulty eyesight, imperceptiveness,
   impercipience, imperfect vision, incognizance, incomprehension,
   insensibility, mindlessness, nearsightedness, nonrealization,
   nonrecognition, nonunderstanding, nystagmus, partial blindness,
   positiveness, purblindness, reduced sight, shortsightedness,
   tunnel vision, unapprehendingness, unawareness, unconsciousness,
   undiscerningness, unmindfulness, unperceptiveness,
   unpersuadableness, unwittingness