quadrant

[ kwod-ruh nt ]

/ ˈkwɒd rənt /

SEE MORE SYNONYMS FOR quadrant ON THESAURUS.COM

noun

a quarter of a circle; an arc of 90°.

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

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

Geometry, Astronomy. one of the four parts into which a plane, as the face of a heavenly body, is divided by two perpendicular lines, numbered counterclockwise from upper right: the first quadrant of the moon.

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

Astrology. one of the four quarters of the horoscope: determined by the ascendant, nadir, descendant, and midheaven and numbered counterclockwise from the ascendant.

Furniture. one of two metal sliding pieces, of quadrant form, used to support the fall front of a desk from above.

Nearby words

Origin of quadrant

1350–1400; Middle English < Latin quadrant- (stem of quadrāns) fourth part

Related formsquad·ran·tal

[kwo-dran-tl] /kwɒˈdræn tl/, adjectivequad·rant·like, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for quadrant

Point it south and it shows you the stars and planets in that quadrant of the sky.
Apps for Kids Who Love to Read: Moonbot Studios, Touch Press, and More|Malcolm Jones|December 24, 2011|DAILY BEAST
People forget all too readily, but Greenspan is a consultant to Pimco, the largest bond manager in this quadrant of the galaxy.
Greenspan's Hidden Agenda|Paul Kedrosky|February 18, 2009|DAILY BEAST
He was expert in the use of quadrant and sextant, and could take a lunar observation and work it out with accuracy.
Siam|George B. Bacon
Pores of the same breadth as the bars, six to eight on the quadrant.
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876, First Part: Porulosa (Spumellaria and Acantharia)|Ernst Haeckel

It is in use on all the ships at the present time, but it has been greatly improved, and is now called the quadrant.
Discoverers and Explorers|Edward R. Shaw
Here, however, comes in now the action of the very beautiful and effective piece of mechanism, "Roberts' quadrant" (see Fig. 26).
The Story of the Cotton Plant|Frederick Wilkinson
Godfrey, the maker of Godfrey's Quadrant, was one of those scientific investigators, and must have been a famous "dialler."
Old-Time Gardens|Alice Morse Earle

British Dictionary definitions for quadrant

quadrant

/ (ˈkwɒdrənt) /

noun

geometry

a quarter of the circumference of a circle
the area enclosed by two perpendicular radii of a circle and its circumference
any of the four sections into which a plane is divided by two coordinate axes

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

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

Derived Formsquadrantal (kwɒˈdræntəl), adjective

Word Origin for quadrant

C14: from Latin quadrāns a quarter

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for quadrant

quadrant

late 14c., "a quarter of a day, six hours," from Middle French quadrant, from Latin quadrantem (nominative quadrans) "fourth part," also the name of a coin worth a quarter of an as, noun use of present participle of quadrare "to make square; put in order, arrange, complete; run parallel, be exact," figuratively "to fit, suit, be proper," related to quadrus "a square," quattuor "four" (see four). The surveying instrument is first so called c.1400, because it forms a quarter circle. Related: Quadrantal.

Medicine definitions for quadrant

quadrant

[ kwŏd′rənt ]

n.

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

A quarter portion of any roughly circular anatomical area such as the abdomen, measuring along imaginary axes at right angles to each other.

Related formsquad•ran′tic (kwŏ-drăn′tĭk) adj.

Science definitions for quadrant

quadrant

[ kwŏd′rənt ]

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

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).

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