quadrant

noun

quad·​rant ˈkwä-drənt 

1

a

: an instrument for measuring altitudes consisting commonly of a graduated arc of 90 degrees with an index or vernier and usually having a plumb line or spirit level for fixing the vertical or horizontal direction

b

: a device or mechanical part shaped like or suggestive of the quadrant of a circle

2

a

: an arc of 90 degrees that is one quarter of a circle

b

: the area bounded by a quadrant and two radii

3

a

: any of the four parts into which a plane is divided by rectangular coordinate axes lying in that plane

b

: any of the four quarters into which something is divided by two real or imaginary lines that intersect each other at right angles

quadrantal

kwä-ˈdran-tᵊl 

adjective

Illustration of quadrant

• quadrant 2

Did you know?

This word is used for a traditional instrument, used to make calculations of altitude and traditionally employed by sailors to navigate, which has a piece shaped like a quarter of a circle. A quadrant shower is a shower that fits snugly into a bathroom corner and displays a curved front, making a quadrant shape on the floor. But perhaps quadrant is used most often today to name a particular quarter of a city.

Examples of quadrant in a Sentence

Draw two intersecting lines that divide the page into four quadrants.

The town is located in the northwest quadrant of the state.

Recent Examples on the Web

After unboxing each electric toothbrush and assessing whether they were already fully charged, testers got to work, gently brushing each quadrant of their mouths. —Emma Guillen, People.com, 17 July 2025

The original plan, initiated by the Washington Square Park Advisory Council, was to close off all four grassy quadrants from September 2025 to spring 2026, making those areas inaccessible to residents for nearly eight months. —Carolyn Stein, Chicago Tribune, 1 June 2025

Other firsts include a smart-glass roof featuring four quadrants for passengers to control opacity, and electronic shutters that obscure screen content while driving and can be controlled remotely via a QR code on the phone. —Jaclyn Trop, Robb Report, 21 May 2025

Most of the northeastern quadrant of the country from Minnesota to Maine was under some type of heat advisory. —Scott Bauer, Twin Cities, 22 June 2025

Word History

Etymology

Middle English, from Latin quadrant-, quadrans fourth part; akin to Latin quattuor four — more at four

First Known Use

15th century, in the meaning defined at sense 1a

Kids Definition

quadrant

noun

quad·​rant ˈkwäd-rənt 

1

: an arc of 90° : one quarter of a circle

2

: any of the four quarters into which something is divided by two real or imaginary lines that intersect each other at right angles

Medical Definition

quadrant

noun

quad·​rant ˈkwäd-rənt 

1

: an arc of 90° that is one quarter of a circle

2

: any of the four more or less equivalent segments into which an anatomic structure may be divided by vertical and horizontal partitioning through its midpoint

pain in the lower right quadrant of the abdomen