The term 'angle 57 degrees' can be expressed in two different ways. The first is as a radian, which is a unit of measurement equal to the angle subtended at the center of a circle by an arc that is equal in length to the radius of the circle. The second way to express this angle is in terms of radians, which is the ratio of the length of the arc to the radius of the circle. Both of these terms are commonly used in mathematics and physics.