Meridian vs. Longitude — What's the Difference?

An imaginary great circle on the earth's surface passing through the North and South geographic poles.

Longitude (, AU and UK also ) is a geographic coordinate that specifies the east–west position of a point on the Earth's surface, or the surface of a celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter lambda (λ).

Either half of such a great circle from pole to pole. All points on the same meridian have the same longitude.

Angular distance on the earth's surface, measured east or west from the Prime Meridian at Greenwich, England, to the meridian passing through a position, expressed in degrees (or hours), minutes, and seconds.

(Astronomy)A great circle passing through the two poles of the celestial sphere and the zenith of a given observer.Also called celestial meridian, local meridian, vertical circle.

Celestial longitude.

A curve on a surface of revolution, formed by the intersection of the surface with a plane containing the axis of revolution.

(geography) Angular distance measured west or east of the prime meridian.

A plane section of a surface of revolution containing the axis of revolution.

Any imaginary line perpendicular to the equator and part of a great circle passing through the North Pole and South Pole.

Any of the longitudinal lines or pathways on the body along which the acupuncture points are distributed.

(archaic) Length.

The highest point in the sky reached by the sun or another celestial body; a zenith.

Length; measure or distance along the longest line; - distinguished from breadth or thickness; as, the longitude of a room; rare now, except in a humorous sense.

The time at which the sun reaches its highest point in the sky; noon.

The arc or portion of the equator intersected between the meridian of a given place and the meridian of some other place from which longitude is reckoned, as from Greenwich, England, or sometimes from the capital of a country, as from Washington or Paris. The longitude of a place is expressed either in degrees or in time; as, that of New York is 74° or 4 h. 56 min. west of Greenwich.

The highest point or stage of development; peak:"Men come to their meridian at various periods of their lives"(John Henry Newman).

The distance in degrees, reckoned from the vernal equinox, on the ecliptic, to a circle at right angles to the ecliptic passing through the heavenly body whose longitude is designated; as, the longitude of Capella is 79°.

Midwestern US See median.

An imaginary great circle on the surface of the earth passing through the north and south poles at right angles to the equator;

Of or relating to a meridian; meridional.

Of or at midday:the meridian hour.

Of, relating to, or constituting the highest point, as of development or power:the empire in its meridian period.

Relating to a meridian (in various senses); meridional.

Relating to midday or noon.

(obsolete)

Relating to the culmination or highest point.

Relating to the south; meridional, southern.

(astronomy)

In full celestial meridian: a great circle passing through the poles of the celestial sphere and the zenith for a particular point on the Earth's surface.

In full terrestrial meridian: a great circle on the Earth's surface, passing through the geographic poles (the terrestrial North Pole and South Pole); also, half of such a circle extending from pole to pole, all points of which have the same longitude.

(by extension)

The place on the celestial meridian where it is crossed by the sun or a star at its highest point.

A ring or half-ring with markings in which an artificial globe is installed and may spin.

(mathematics) A line passing through the poles of any sphere; a notional line on the surface of a curved or round body (in particular, an eyeball).

The size of type between double great primer and canon, standardized as 44-point.

(obsolete)

The south.

Midday, noon.

A midday rest; a siesta.

A particular area or situation considered as having a specific characteristic or identity; also, the characteristics, habits, or tastes of a specific group, locale, etc.

(Scotland) An alcoholic drink taken at midday.

Any of the pathways on the body along which chi or qi (life force) is thought to flow and, therefore, the acupoints are distributed; especially, one of twelve such pathways associated with organs of the body.

(transitive) To cause an object to reach the meridian or highest point of (something).

(intransitive) Of a celestial body: to reach its meridian.

Being at, or pertaining to, midday; belonging to, or passing through, the highest point attained by the sun in his diurnal course.

Pertaining to the highest point or culmination; as, meridian splendor.

Midday; noon.

Hence: The highest point, as of success, prosperity, or the like; culmination.

A great circle of the sphere passing through the poles of the heavens and the zenith of a given place. It is crossed by the sun at midday.

A great circle on the surface of the earth, passing through the poles and any given place; also, the half of such a circle included between the poles.

A town in eastern Mississippi

An imaginary great circle on the surface of the earth passing through the north and south poles at right angles to the equator;

Of or happening at noon;