meridional aberration

me·rid·i·o·nal ab·er·ra·tion

an aberration produced in the plane of a single meridian of a lens.

me·rid·i·o·nal ab·er·ra·tion

(mĕ-rid'ē-ŏ-năl ab-ĕr-ā'shŭn)
An aberration produced in the plane of a single meridian of a lens.