quadrant

quad·rant  (kwdrnt)

n.

1. Mathematics

a. A circular arc of 90°; one fourth of the circumference of a circle.

b. The plane area bounded by such an arc and two perpendicular radii.

c. Any of the four areas into which a plane is divided by the reference axes in a Cartesian coordinate system, designated first, second, third, and fourth, counting counterclockwise from the area in which both coordinates are positive.

2. A machine part or other mechanical device that is shaped like a quarter circle.

3. An early instrument for measuring altitude of celestial bodies, consisting of a 90° graduated arc with a movable radius for measuring angles.

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[Middle English, quarter of a day, from Latin quadrns, quadrant-, a fourth part; see k^wetwer- in Indo-European roots.]

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quadrant

Noun

1. Geom

a. a quarter of the circumference of a circle

b. the area enclosed by two perpendicular radii of a circle

2. a piece of a mechanism in the form of a quarter circle

3. an instrument formerly used in astronomy and navigation for measuring the altitudes of stars [Latin quadrans a quarter]

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quadrant  (kwdrnt)

1. An arc equal to one quarter of the circumference of a circle; an arc of 90°.

2. Any of the four regions into which a plane is divided by the axes of a Cartesian coordinate system. The quadrants are numbered counterclockwise one through four, beginning with the quadrant in which both the x- and y-coordinates are positive (usually the upper right quadrant).

3. A navigational instrument similar to a sextant but with an arc of 90° rather than 60°. See more at sextant.

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quadrant

an instrument for measuring angular elevation, used in astronomy, navigation, surveying, etc., similar in principle to the sextant. — quadrantal, ad].

See also: Instruments

Thesaurus

Noun	1.	quadrant - a quarter of the circumference of a circle quarter-circle line - a spatial location defined by a real or imaginary unidimensional extent
	2.	quadrant - any of the four areas into which a plane is divided by two orthogonal coordinate axes area, country - a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography); "it was a mountainous area"; "Bible country"
	3.	quadrant - the area enclosed by two perpendicular radii of a circle area, country - a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography); "it was a mountainous area"; "Bible country"
	4.	quadrant - a measuring instrument for measuring altitude of heavenly bodies measuring device, measuring instrument, measuring system - instrument that shows the extent or amount or quantity or degree of something