ra
dius
Plural
radii
1
the length of a straight line drawn from the center of a circle to any point on its outer boundary
- The radius of a circle is half the length of its diameter, extending from the center to any point on the circumference.
- A compass is a tool used to draw circles, with the radius adjusted to the desired measurement.
- The architect calculated the radius of the dome to ensure its proportions were aesthetically pleasing.
- In geometry, the area of a circle can be calculated using the formula π× radius squared.
- The radius of a planet determines its gravitational influence and orbital characteristics within a solar system.
Synonyms:
2
a supporting radial member of a wheel connecting the hub to the rim
- The bicycle's radius snapped during the ride.
- Mechanics replaced a damaged radius on the wheel.
- Each radius must be tensioned correctly for balance.
- The radius holds the rim firmly in place.
- The spoked wheel consists of multiple radii.
Synonyms:
3
a circular region defined by the distance from its center, indicated by the radius
- The park has a radius of 100 meters from the central fountain.
- Emergency services cover a radius of 10 kilometers.
- The signal reaches a radius of 500 meters.
- The study focused on a radius around the city center.
- The blast affected a radius of several hundred meters.
4
the outer and slightly shorter of the two bones of the human forearm
The radius is one of the two bones in the lower arm, along with the ulna. The radius plays a crucial role in forearm rotation and wrist movement, allowing for supination and pronation of the hand. It also supports the muscles of the forearm and provides attachment points for ligaments and tendons involved in arm and hand movements. The radius's position and structure contribute to the overall strength and stability of the arm, enabling a wide range of activities such as lifting, gripping, and manipulating objects with precision.
- He fractured his radius during the fall.
- X-rays showed a clean break of the radius.
- The radius runs parallel to the ulna.
- Doctors set the radius before casting.
- Strength exercises help protect the radius.