1. [ noun ] (geometry) the length of a line segment between the center and circumference of a circle or sphere
Synonyms: r
Related terms: length radius_of_curvature semidiameter diameter
2. [ noun ] a circular region whose area is indicated by the length of its radius

"they located it within a radius of 2 miles"

Related terms: region
3. [ noun ] (mathematics,geometry) a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)
Related terms: straight_line
4. [ noun ] (anatomy,zoology) the outer and slightly shorter of the two bones of the human forearm
Related terms: arm_bone forearm
5. [ noun ] support consisting of a radial member of a wheel joining the hub to the rim
Synonyms: spoke
Related terms: support cartwheel wagon_wheel bicycle_wheel
Similar spelling:   Rattus