radius

• Nom désignant un segment allant du centre à la circonférence d'un cercle ou d'une sphère, ainsi que l'os de l'avant-bras ou le rayon d'une roue.

A noun referring to a line segment from the center to the circumference of a circle or sphere, or the bone in the forearm, or a spoke of a wheel.

pluriel irrégulier

1. Distance from centerB1formalscientific

   The length of a straight line from the center of a circle or sphere to its outer edge or surface.

   rayon (distance du centre)

   • The radius of the circle is five centimeters.
   • To find the area, multiply pi by the square of the radius.
   • The satellite orbits at a radius of 200 kilometers.

   Synonymessemidiameter

2. Circular areaB2formalscientific

   A circular region defined by the distance from a central point.

   Zone circulaire

   • The explosion affected everything within a one-mile radius.
   • The school serves students within a five-kilometer radius.
   • They searched the area within a 10-mile radius of the crash site.

   Synonymesareacirclerangeregionzone

3. Forearm boneB2formalmedical

   The outer and slightly shorter of the two bones in the human forearm, located on the thumb side.

   Radius (os de l'avant-bras)

   • He fractured his radius in a fall.
   • The radius and ulna are the two bones of the forearm.
   • The doctor examined the radius for signs of injury.

4. Wheel spokeB2formaltechnical

   A supporting rod or bar that connects the center of a wheel to its outer rim.

   Rayon de roue

   • The wheel's radius was bent in the accident.
   • Each radius of the wheel is made of strong steel.
   • The mechanic replaced the damaged radius on the bicycle wheel.

   Synonymesspoke