Radius definition

(1) Support consisting of a radial member of a wheel joining the hub to the rim

(2) The length of a line segment between the center and circumference of a circle or sphere

(3) The outer and slightly shorter of the two bones of the human forearm

(4) A circular region whose area is indicated by the length of its radius

"They located it within a radius of 2 miles"

(5) A straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)