verb (used with object)

to subject to refraction.
to determine the refractive condition of (an eye).

Origin of refract

1605–15; < Latin refrāctus, past participle of refringere to break, force back, equivalent to re- re- + frac- (variant stem of frangere to break) + -tus past participle suffix
Related formsre·fract·a·ble, adjectivere·fract·ed·ly, adverbre·fract·ed·ness, nounnon·re·fract·ing, adjectiveun·re·fract·ed, adjectiveun·re·fract·ing, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for refract

Historical Examples of refract

  • “Well, I hope it will refract some of the gold when we get there,” said Mark.

    Dead Man's Land

    George Manville Fenn

  • Because they refract the rays of light in the same manner as the rain drops.

  • Because the light vapours of the air, which are condensed as the sun sets, refract the rays of light, and produce red rays.

  • Ions in the air act like drops of mist; they refract sunshine and make rainbows after rain.

    Operation Terror

    William Fitzgerald Jenkins

  • In the mean while another Prism abc is to be fixed next after that hole g, to refract the trajected Light a second time.


    Isaac Newton

British Dictionary definitions for refract


verb (tr)

to cause to undergo refraction
to measure the refractive capabilities of (the eye, a lens, etc)
Derived Formsrefractable, adjective

Word Origin for refract

C17: from Latin refractus broken up, from refringere, from re- + frangere to break
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for refract

"to bend" (light, sound, heat, etc.), 1610s, back-formation from refraction, and in part from Latin refractus, past participle of refringere. Related: Refracted; refracting.

Online Etymology Dictionary, © 2010 Douglas Harper

refract in Medicine




To deflect something, especially light, from a straight path by refraction.
To determine the refraction of an eye or a lens.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.