Axis (Geometry) Definition

Axis is defined as an invisible or imaginary line on which an object moves or rotates. Coordinate systems are used to determine the property or position of an object located on these axes—points where an axis crosses an object's surface are called north and south poles.

To determine two-dimensional objects, the x-axis and y-axis are used in coordinate planes. In contrast, for three-dimensional objects, the x-axis, y-axis and z-axis are used in coordinate planes. In a real-life example, take earth which rotates around its axis.

For a more precise understanding of this, check out the example below: