What is "azimuth"

Azimuth \Az"i*muth\, n. [OE. azimut, F. azimut, fr. Ar. as-sum?t, pl. of as-samt a way, or perh., a point of the horizon and a circle extending to it from the zenith, as being the Arabic article: cf. It. azzimutto, Pg. azimuth, and Ar. samt-al-r[=a]'s the vertex of the heaven. Cf. Zenith.] (Astron. & Geodesy)

1. The quadrant of an azimuth circle.

2. An arc of the horizon intercepted between the meridian of the place and a vertical circle passing through the center of any object; as, the azimuth of a star; the azimuth or bearing of a line surveying.

   Note: In trigonometrical surveying, it is customary to reckon the azimuth of a line from the south point of the horizon around by the west from 0[deg] to 360[deg].

   Azimuth circle, or Vertical circle, one of the great circles of the sphere intersecting each other in the zenith and nadir, and cutting the horizon at right angles.
   --Hutton.

   Azimuth compass, a compass resembling the mariner's compass, but having the card divided into degrees instead of rhumbs, and having vertical sights; used for taking the magnetic azimuth of a heavenly body, in order to find, by comparison with the true azimuth, the variation of the needle.

   Azimuth dial, a dial whose stile or gnomon is at right angles to the plane of the horizon.
   --Hutton.

   Magnetic azimuth, an arc of the horizon, intercepted between the vertical circle passing through any object and the magnetic meridian. This is found by observing the object with an azimuth compass.

"distance of a star from the north or south point of the meridian," late 14c., from Old French azimut, from Arabic as-sumut "the ways," plural of as-samt "the way, direction" (see zenith).

n. 1 An arc of the horizon intercepted between the meridian of the place and a vertical circle passing through the center of any object; as, the azimuth of a star; the azimuth or bearing of a line surveying. 2 The quadrant of an azimuth circle.

n. the azimuth of a celestial body is the angle between the vertical plane containing it and the plane of the meridian [syn: AZ]

An azimuth (from Arabic al-sumūt, meaning "the directions") is an angular measurement in a spherical coordinate system. The vector from an observer ( origin) to a point of interest is projected perpendicularly onto a reference plane; the angle between the projected vector and a reference vector on the reference plane is called the azimuth.

An example is the position of a star in the sky. The star is the point of interest, the reference plane is the horizon or the surface of the sea, and the reference vector points north. The azimuth is the angle between the north vector and the perpendicular projection of the star down onto the horizon.

Azimuth is usually measured in degrees (°). The concept is used in navigation, astronomy, engineering, mapping, mining and artillery.

Azimuth was a British jazz trio, active from 1977 to 2000. The ensemble was composed of trumpeter Kenny Wheeler, vocalist Norma Winstone and Winstone's husband, pianist John Taylor. Their first release under this name was a 1977 album issued on ECM Records; two further albums quickly followed, with later albums coming in 1985 and 1995.

Azimuth is the debut album by British jazz trio Azimuth featuring trumpeter Kenny Wheeler, vocalist Norma Winstone, and pianist John Taylor recorded in 1977 and released on the ECM label.