Final answer:
Astigmatism is a vision disorder caused by a misshapen cornea, leading to uneven focus and potentially elongated or blurred images. It can be corrected with cylindrical lenses tailored to counteract the corneal irregularities.
Step-by-step explanation:
The vision disorder due to a misshapen cornea is c) astigmatism. Astigmatism is characterized by an unevenness or asymmetry in the focus of the eye, leading to images that can appear elongated or blurred. This condition is primarily caused by irregularities in the shape of the cornea, although it can also be a result of lens irregularities or variations in the retina.
Rays of light passing through different regions of the cornea may focus at varying distances, which could produce images at different locations on the retina, often resulting in less distinct vision. Astigmatism can be corrected with spectacles that have a cylindrical correction to counterbalance the eye's irregularities. Unlike the spherical corrections used for addressing short-sightedness (myopia) or far-sightedness (hyperopia), cylindrical corrections are specific to correcting astigmatism.