Main Entry:

astig·ma·tism

Pronunciation:

\ə-ˈstig-mə-ˌti-zəm\

Function:

noun

Date:

1846

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 especially to corneal irregularity 3 : distorted understanding suggestive of the blurred vision of an astigmatic person