quad·rant

(kwŏd′rənt)

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.

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

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

quadrant

(ˈkwɒdrənt)

1. (Mathematics) geometry

a. a quarter of the circumference of a circle

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

c. any of the four sections into which a plane is divided by two coordinate axes

2. (Mechanical Engineering) a piece of a mechanism in the form of a quarter circle, esp one used as a cam or a gear sector

3. (Astronomy) an instrument formerly used in astronomy and navigation for measuring the altitudes of stars, consisting of a graduated arc of 90° and a sighting mechanism attached to a movable arm

[C14: from Latin quadrāns a quarter]

quadrantal adj

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

quad•rant

(ˈkwɒd rənt)

n.

1. a quarter of a circle; an arc of 90°.

2. the area included between such an arc and two radii drawn one to each extremity.

3. something shaped like a quarter of a circle, as a part of a machine.

4. one of the four parts into which a plane, as the face of a heavenly body, is divided by two perpendicular lines: the first quadrant of the moon.

5. an instrument, usu. containing a graduated arc of 90°, used in astronomy, navigation, etc., for measuring altitudes.

[1350–1400; Middle English < Latin quadrant-, s. of quadrāns fourth part]

quad·rant

(kwŏd′rənt)

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. An instrument with an arc of 90°, used to measure the angle between a celestial object and the horizon.

The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

quadrant

- A quarter of a circle or sphere.

quadrant

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

quadrant

[ˈkwɒdrənt] N → cuadrante m

Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

quadrant

[ˈkwɒdrənt] n → quadrant m

Collins English/French Electronic Resource. © HarperCollins Publishers 2005

quadrant

n → Quadrant m

Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

quadrant

[ˈkwɒdrənt] n → quadrante m

Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

quad·rant

n. cuadrante, cuarta parte de un círculo.

English-Spanish Medical Dictionary © Farlex 2012

quadrant

n cuadrante m; left lower — cuadrante inferior izquierdo right upper — cuadrante superior derecho

Mentioned in

References in classic literature

Well that Ahab's quadrant was furnished with colored glasses, through which to take sight of that solar fire.

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She led him into the forbidden quadrant. An abrupt mountain, shouldering in from the north to meet a similar intrusion from the south, tormented the stream in which they had fished into a deep and gloomy gorge.

In company with Balatta, sometimes with men and parties of women, the freedom of the jungle was his for three quadrants of the compass.

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Before long he knew where Disko kept the old green-crusted quadrant that they called the "hog-yoke" - under the bed-bag in his bunk.

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Under that, the miscellany began--a quadrant, a tin canikin, several sticks of tobacco, two brace of very handsome pistols, a piece of bar silver, an old Spanish watch and some other trinkets of little value and mostly of foreign make, a pair of compasses mounted with brass, and five or six curious West Indian shells.

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Some time after, asking a friend at court how they came to fix on that determinate number, he told me that his majesty's mathematicians, having taken the height of my body by the help of a quadrant, and finding it to exceed theirs in the proportion of twelve to one, they concluded from the similarity of their bodies, that mine must contain at least 1724 of theirs, and consequently would require as much food as was necessary to support that number of Lilliputians.

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He took a wife, as we have seen, to adorn the remaining quadrant of his course, and be a little moon that would cause hardly a calculable perturbation.

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Whenever this powdered and courteous old man, who never missed a Sunday at the convent chapel at Hammersmith, and who was in all respects, thoughts, conduct, and bearing utterly unlike the bearded savages of his nation, who curse perfidious Albion, and scowl at you from over their cigars, in the Quadrant arcades at the present day-- whenever the old Chevalier de Talonrouge spoke of Mistress Osborne, he would first finish his pinch of snuff, flick away the remaining particles of dust with a graceful wave of his hand, gather up his fingers again into a bunch, and, bringing them up to his mouth, blow them open with a kiss, exclaiming, Ah!

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He lost himself amongst advancing semi-circles, left- and right-hand quadrants, the curves of the tracks, the probable bearing of the centre, the shifts of wind and the readings of barometer.

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Metro Manila has been divided into four quadrants with their own staging areas:

Upcoming Metro Manila shake drill aims to be 'realistic'

- Magic Quadrant for Unified Communications : This is the eleventh year in a row Gartner named Cisco a Leader in this Magic Quadrant.

Cisco Named a Leader in Three Gartner Magic Quadrant Reports in Four Months

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