diplopia

diplopia /diplō″pē·ə/ [Gk, diploos + opsis, vision] , double vision caused by defective function of the extraocular muscles or a disorder of the nerves that innervate the muscles. It occurs when the object of fixation falls on the fovea in one eye and a nonfoveal point in the other eye or when the object of fixation falls on two noncorresponding points. Also called ambiopia, double vision. Compare binocular vision.