quadrant

quadrant, in analytic geometry

quadrant.

1 In analytic geometry, one of the four regions of the plane determined by two lines, the x-axis and the y-axis. Commonly these lines are drawn perpendicular to each other, and the quadrants, or regions, they determine are numbered counterclockwise, beginning with the upper right quadrant.

2 In geometry, a region of a plane determined by two perpendicular radii of a circle and the circle itself. Thus two perpendicular diameters of a circle divide it into four regions, or quadrants.

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quadrant, in technology

quadrant, in technology, angle-measuring device based on a scale of 90°. It is sometimes confused with the sextant, a similar instrument based on a scale of 60°. The quadrant is rarely used today.

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quadrant

1. 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. a piece of a mechanism in the form of a quarter circle, esp one used as a cam or a gear sector

3. 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

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quadrant [′kwä·drənt]

(anatomy)

One of the four regions into which the abdomen may be divided for purposes of physical diagnosis.

(electromagnetism)

international henry

(engineering)

An instrument for measuring altitudes, used, for example, in astronomy, surveying, and gunnery; employs a sight that can be moved through a graduated 90° arc.

A lever that can move through a 90° arc.

(mathematics)

A quarter of a circle; either an arc of 90° or the area bounded by such an arc and the two radii.

Any of the four regions into which the plane is divided by a pair of coordinate axes.

(mechanical engineering)

A device for converting horizontal reciprocating motion to vertical reciprocating motion.

(navigation)

One of the four areas between consecutive equisignal zones of a four course radio range station.

(naval architecture)

A casting, forging, or built-up frame in the shape of a sector of a circle attached to the rudder stock and through which the steering gear leads turn the rudder.

(optics)

A double-reflecting instrument for measuring angles, used primarily for measuring altitudes of celestial bodies; the instrument was replaced by the sextant.

(physiology)

A sector of one-fourth of the field of vision of one or both eyes.