Definition of refract in English:



  • 1 (of water, air, or glass) make (a ray of light) change direction when it enters at an angle.

    ‘the rays of light are refracted by the material of the lens’
    • ‘The hotter, denser air refracts the light coming from the horizon and the viewer sees an image of the sky near the horizon.’
    • ‘The cornea and the crystalline lens refract light that enters the eye.’
    • ‘The rays were detected by a calcium sulfide thread that glowed slightly in the dark when the rays were refracted through a 60-degree angle prism of aluminum.’
    • ‘Not only is the roof above them made of glass, it is also filled with water, further refracting the light received in the public spaces below.’
    • ‘The image passes through the lens, which further refracts the light through its anterior and posterior curvatures.’
    • ‘When the temperature difference is large enough, the warmer air refracts the light and amazing images can be seen.’
    • ‘The regional variation of ocean depth acts as a lens to refract the waves, just as a lens refracts light.’
    • ‘A light ray is refracted when it passes from one medium to another at an angle and its speed changes.’
    • ‘Sparkling glass goblets and mugs refracted the light just as the silver reflected it.’
    • ‘It acted like a prism on the setting sunlight striking it, refracting the light in much the same way as a crystal would.’
    • ‘In particular, this initial work has demonstrated the enormous potential for a new generation of lenses, which function, of course, by refracting the rays of incident waves.’
    • ‘Ideally we would like to refract the shadow ray too, but mathematically this is a much more difficult problem to solve.’
    • ‘Color is important: one sees the reds, tans and browns of skin color, the blue of water and the wavy white lines of light refracted through the water.’
    • ‘In De Natura Locorum he gives a diagram which shows light being refracted by a spherical glass container full of water.’
    • ‘Spectacles and contact lenses refract the light before it enters the eye, helping the eye to focus objects sharply.’
    • ‘The cornea and lens refract the incoming light rays to focus them on the retina at the back of the eye.’
    • ‘They cut glass, they refract light into perfect hearts-and-arrows, and they have superlative fire and brilliance.’
    • ‘This is because of particles in the air refracting the light.’
    • ‘The wavelength of light affects how much it is refracted on entering the atmosphere, with red light refracted the most and blue least (as in rainbows).’
    • ‘Metamaterial research is an emerging field that uses manmade substances to alter the way materials refract light or electromagnetic radiation.’
    1. 1.1Measure the focusing characteristics of (an eye) or of the eyes of (someone)
      ‘when refracting patients an ophthalmologist relies on verbal reports’


Early 17th century: from Latin refract- broken up, from the verb refringere, from re- back + frangere to break.