One of the four sections made by dividing an area with two perpendicular lines.
One fourth of a circle or disc; a sector with an angle of 90°.
One of the four regions of the Cartesian plane bounded by the x-axis and y-axis.
A measuring device with a graduated arc of 90° used in locating an altitude.
One of the four categories of team wins and losses, as categorized by strength of schedule.
A polygon with four sides.
An area defended by four fortresses supporting each other.
Having four sides.