refract

Of a medium, substance, object, etc.: to deflect the course of (light rays), esp. when they enter the medium, etc., at an oblique angle; to cause refraction of (light, other electromagnetic radiation, or sound or other wave phenomena).

To mediate; to alter; to distort.

To cause (light) to change direction as a result of entering a different medium.

To measure, and often also to correct with lenses, the refractive error of (an eye) or the eyes of (a person).

A prism can refract light.