noon
The time of day at which the Sun crosses the local meridian and is at its highest point above the horizon. This time differs from 12.00 local time by up to about 15 minutes before or after midday, the amount – the equation of time – depending on the time of year.Collins Dictionary of Astronomy © Market House Books Ltd, 2006
noon
[nün] (astronomy)
The instant at which a time reference is over the upper branch of the reference meridian.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
noon
The time at which the center of the sun transits a particular meridian.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
Noon
the moment at which, for a given point on earth, the center of the sun (the true sun or the mean sun) is in the upper culmination. The apparent noon corresponds to a meridian transit by the true sun, while mean noon corresponds to a transit by the mean sun. The time at which noon occurs depends on the geographic longitude. Noon begins one hour later for every 15° of longitude to the west.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.