QUADRANT

noun see: four Date: 15th century 1. 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, a device or mechanical part shaped like or suggestive of the ~ of a circle, 2. an arc of 90 degrees that is one quarter of a circle, the area bounded by a ~ and two radii, 3. any of the four parts into which a plane is divided by rectangular coordinate axes lying in that plane, any of the four quarters into which something is divided by two real or imaginary lines that intersect each other at right angles, ~al adjective