The Collaborative International Dictionary of English v.0.48:

Strabismus \Stra*bis"mus\, n. [NL., fr. Gr. ?, fr. ? to squint,
   fr. ? distorted, squinting.] (Med.)
   An affection of one or both eyes, in which the optic axes can
   not be directed to the same object, -- a defect due either to
   undue contraction or to undue relaxation of one or more of
   the muscles which move the eyeball; squinting; cross-eye.
   [1913 Webster]

WordNet (r) 3.0 (2006):

strabismus
    n 1: abnormal alignment of one or both eyes [syn: strabismus,
         squint]