The prescription you received from the eye specialist contains a number of values.
The SPH value (Sphere) indicates your nearsightedness (-minus) and/or farsightedness (+plus).
The CYL and AXI values (C cylinder & A axis) indicate Astigmatism. CYL indicates the lens power needed to correct it, and AXI indicates the curvature of your cornea. A number between 1 and 180 degrees.
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