1. (noun) the length of a line segment between the center and circumference of a circle or sphere

• r

2. (noun) support consisting of a radial member of a wheel joining the hub to the rim

• spoke
• wheel spoke

1. (noun) the length of a line segment between the center and circumference of a circle or sphere

• length

2. (noun) a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)

• straight line

3. (noun) a circular region whose area is indicated by the length of its radius

• part
• region

4. (noun) the outer and slightly shorter of the two bones of the human forearm

• arm bone

5. (noun) support consisting of a radial member of a wheel joining the hub to the rim

• support

1. (noun) the length of a line segment between the center and circumference of a circle or sphere

• radius of curvature
• semidiameter

1. (noun) a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)

• radial

2. (noun) the outer and slightly shorter of the two bones of the human forearm

• radial