• noun the apparent bending of light or sound that occurs when it travels through a material


  • The change in path of a light ray or energy wave as it passes obliquely from one medium to another.


  • The process via which a wave abruptly changes direction when passing from a medium within which it has one propagation velocity, into another in which it has a different propagation velocity. The ray entering the second medium is the incident ray, while the refracted ray is that resulting after bending. For example, a light ray passing at an angle from air into glass is refracted, as light travels more slowly through glass. Other forms of electromagnetic radiation, such as microwaves or X-rays may also be refracted, in addition to sound waves. Also, the effect refraction has on a wave.

Media Studies

  • noun the change in direction that occurs when a wave of energy such as light passes from one medium to another of a different density, e.g. through a lens
  • noun the ability of the eye or a lens to change the direction of light in order to focus it


  • noun a change of direction of light rays as they enter a medium such as the eye
  • noun the measurement of the angle at which the light rays bend, as a test to see if someone needs to wear glasses