An eye in which the iris is of a very light gray or whitish color; said usually of horses. Note: Jonson has defined wall-eye to be "a disease in the crystalline humor of the eye; glaucoma." But glaucoma is not a disease of the crystalline humor, nor is wall-eye a disease at all, but merely a natural blemish. In the north of England, as Brockett states, persons are said to be wall-eyed when the white of the eye is very large and distorted, or on one side.