[astig.ma.tism] n (1849) 1: a defect of an optical system (as a lens) causing rays from a point to fail to meet in a focal point resulting in a blurred and imperfect image
2: a defect of vision due to astigmatism of the refractive system of the eye and esp. to corneal irregularity
3: distorted understanding suggestive of the blurred vision of an astigmatic person