Noon (also midday) is the hour of 12:00 pm (1200) in an observer's local time zone, or more loosely, a time near the middle of the day when workers in many countries take a meal break. The scientific term solar noon describes the moment when the sun crosses the meridian in apparent solar time. Solar times are measures of the apparent position of the Sun on the Celestial sphere.
The opposite of noon is midnight. In Lexical semantics, opposites are words that lie in an inherently incompatible binary relationship as in the opposite pairs male: female, long: short Midnight is literally "the middle of the night" In most systems it is when one day ends and the next begins when the date changes
The word "noon" is derived from Latin nona hora, the ninth hour of the day. The Roman and Western European medieval monastic day began at 6:00 am (0600) by modern timekeeping, so the ninth hour began at what is now 2:00 pm (1400). In English, the meaning of the word shifted to midday by the year 1100 CE. 
Solar noon is the moment when the sun appears the highest in the sky (nearest zenith), compared to its positions during the rest of the day. The sky is the part of the Atmosphere or of Outer space visible from the surface of any Astronomical object. In broad terms the zenith is the direction pointing directly above a particular location ( Perpendicular, Orthogonal) It occurs when the Sun is transitting the celestial meridian. The term transit or astronomical transit has three meanings in astronomy A transit is the astronomical event that occurs when one Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study This article is about the astronomical concept For other uses of the word see Meridian. This is also the origin of the terms ante meridiem and post meridiem as noted above. The Sun is directly overhead at solar noon at the equator on the equinoxes; at Tropic of Cancer (latitude 23° 26′ 22″ N) on the June solstice; and at Tropic of Capricorn (23° 26′ 22″ S) on the December solstice. The equator (sometimes referred to colloquially as "the Line") is the intersection of the Earth 's surface with the plane perpendicular to the An equinox is the event of the Sun passing over the Earth's equator in its annual cycle For the novel by Henry Miller, see Tropic of Cancer (novel. The Tropic of Cancer, or Northern tropic, is one of five Latitude, usually denoted symbolically by the Greek letter phi ( Φ) gives the location of a place on Earth (or other planetary body north or south of the Solstices occur twice a year when the tilt of the Earth's axis is most oriented toward or away from the Sun, causing the Sun to reach its northernmost and southernmost extremes For the novel by Henry Miller, see Tropic of Capricorn (novel. Due to the effects of the use of standard time, daylight saving time, and the equation of time, clock noon and solar noon rarely coincide. Standard time is the result of synchronizing clocks in different geographical locations within a Time zone to the same time rather than using the local meridian as Daylight saving time ( DST The equation of time is the difference over the course of a year between time as read from a Sundial and time as read from a Clock, measured in an ideal situation