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Also called a·stig·mi·a[uh-stig-mee-uh]. /əˈstɪg mi ə/. Ophthalmology. a refractive error of the eye in which parallel rays of light from an external source do not converge on a single focal point on the retina.
Optics. an aberration of a lens or other optical system in which the image of a point is spread out along the axis of the system.
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SHALL WE PLAY A "SHALL" VS. "SHOULD" CHALLENGE?
Should you take this quiz on “shall” versus “should”? It should prove to be a quick challenge!
Question 1 of 6
Which form is used to state an obligation or duty someone has?
A visual defect in which the unequal curvature of one or more refractive surfaces of the eye, usually the cornea, prevents light rays from focusing clearly at one point on the retina, resulting in blurred vision.astigmia
A visual defect in which the unequal curvature of one or more refractive surfaces of the eye, usually the cornea, prevents light rays from focusing clearly at a single point on the retina, resulting in blurred vision.