radius

noun

1. 1

   The long bone in the forearm, on the side of the thumb.

2. 2

   The lighter bone (or fused portion of bone) in the forelimb of an animal.

3. 3

   One of the major veins of the insect wing, between the subcosta and the media; the vein running along the costal edge of the discal cell.

4. 4

   A line segment between any point of a circle or sphere and its center.

5. 5

   The length of this line segment.

6. 6

   Anything resembling a radius, such as the spoke of a wheel, the movable arm of a sextant, or one of the radiating lines of a spider's web.