Stigmatism

Stigmatism, often misspelled as "stigmatism," refers to a visual defect known as astigmatism. Astigmatism is a common refractive error caused by an irregular shape of the cornea or lens in the eye. Instead of having a perfectly rounded shape, the cornea or lens may be shaped more like a football or an egg, which results in light rays being focused at multiple points, rather than converging at a single point on the retina.