noun
- a unit of angular measurement equal to the angle subtended at the center of a circle by an arc whose length equals the radius
Usage: mathematics; geometry
Examples
- A full circle contains 2π radians.
- Convert 90 degrees to radians by multiplying by π/180.
- The angle measured 1.5 radians.
- Trigonometric functions in calculus typically use radians.
- One radian equals approximately 57.3 degrees.
- The arc length formula uses radians for the angle measurement.