a quarter of the circumference of a circle
the area of one quarter of a circle that is bounded by an arc containing an angle of 90°
any of the four quarters into which something is divided by two real or imaginary lines that intersect each other at right angles
an instrument for measuring angles, usu consisting of a graduated arc of 90°
a device or mechanical part shaped like or suggestive of the quadrant of a circle
quadrantal /kwoʹdrantl/ adj
[Middle English from Latin quadrant-, quadrans fourth part, from quattuor four]