noun
radius
The bone on the thumb side of the forearm.
The diagram shows the radius beside the ulna.
Etymology
Latin radius means a rod or spoke. Anatomy applied that shape-based name to the long bone on the thumb side of the forearm.
More examples
- The fracture involved the lower end of the radius.
- The radius rotates as the forearm turns.
- The anatomy model labels both radii.
Forms
radius · radii · radiuses
Similar words
- ulna
- The neighboring forearm bone on the little-finger side.