radius

Short definition from Wiktionary

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.
7. 7
   The minimum eccentricity of any vertex, for a given graph.
8. 8
   Initialism of Remote Authentication Dial-In User Service.

Verb

1. 1
   To give a rounded edge to.