a. Twelve o'clock in the daytime; midday.
b. The time or point in the sun's path at which the sun is on the local meridian. Also called noontide, noontime.
2. The highest point; the zenith.
3. Archaic Midnight.
[Middle English non, from Old English nōn, canonical hour of nones (3 PM in early Middle Ages), from Late Latin nōna (hōra), ninth (hour after sunrise), nones, feminine sing. of Latin nōnus, ninth; see new in the Appendix of Indo-European roots.]
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