Illustrations of a circle with segment, semicircle, sector, quadrant, and central angles drawn.

"A quadrant, or one fourth of a circle. The oblique lines indicate various angles with the base. The…

"Elevation and section of Thomson's Quadrant Electrometer." — Encyclopedia Britannica, 1893

A point lies in the first quadrant if the plan lies below, the elevation above the axis; in the second…

"QUARTERED. A shield divided into four equal parts by a cross is said to be quartered. The quarter occupying…

A sphere with quadrants and poles. "A point on the surface of a sphere, which is at the distance of…