The Collaborative International Dictionary of English v.0.48:

Ophthalmologist \Oph`thal*mol"o*gist\, n.
   One skilled in ophthalmology; an oculist.
   [1913 Webster]

WordNet (r) 3.0 (2006):

ophthalmologist
    n 1: a medical doctor specializing in the diagnosis and
         treatment of diseases of the eye [syn: ophthalmologist,
         eye doctor, oculist]