Me‐rid″i‐an (?), a. [F. méridien, L. meridianus pertaining to noon, fr. meridies noon, midday, for older medidies; medius mid, middle + dies day. See Mid, and Diurnal.] 1. Being at, or pertaining to, midday; belonging to, or passing through, the highest point attained by the sun in his diurnal course. “Meridian hour.” Milton.
Tables... to find the altitude meridian. Chaucer.
2. Pertaining to the highest point or culmination; as, meridian splendor.