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diffraction

[dih-frak-shuh n]
noun Physics.
  1. the phenomenon exhibited by wave fronts that, passing the edge of an opaque body, are modulated, thereby causing a redistribution of energy within the front: it is detectable in light waves by the presence of a pattern of closely spaced dark and light bands (diffraction pattern) at the edge of a shadow.
  2. the bending of waves, especially sound and light waves, around obstacles in their path.

Origin of diffraction

1665–75; < New Latin diffrāctiōn- (stem of diffrāctiō) a breaking up, equivalent to Latin diffrāct(us) broken up (past participle of diffringere) + -iōn- -ion. See dif-, fraction
Can be confuseddiffraction diffusion reflection rarefaction refraction
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for diffraction pattern

diffraction pattern

noun
  1. physics the distinctive pattern of light and dark fringes, rings, etc, formed by diffraction

diffraction

noun
  1. physics a deviation in the direction of a wave at the edge of an obstacle in its path
  2. any phenomenon caused by diffraction and interference of light, such as the formation of light and dark fringes by the passage of light through a small aperture
  3. deflection of sound waves caused by an obstacle or by nonhomogeneity of a medium

Word Origin for diffraction

C17: from New Latin diffractiō a breaking to pieces, from Latin diffringere to shatter, from dis- apart + 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 diffraction pattern

diffraction

n.

1670s, from French diffraction (17c.) or directly from Modern Latin diffractionem (nominative diffractio), noun of action from past participle stem of Latin diffringere "break in pieces," from dis- "apart" (see dis-) + frangere "to break" (see fraction).

Online Etymology Dictionary, © 2010 Douglas Harper
diffraction pattern in Medicine

diffraction

[dĭ-frăk′shən]
n.
  1. Change in the directions and intensities of a group of waves after passing by an obstacle or through an aperture.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
diffraction pattern in Science

diffraction pattern

  1. The interference pattern that results when a wave or a series of waves undergoes diffraction, as when passed through a diffraction grating or the lattices of a crystal. The pattern provides information about the frequency of the wave and the structure of the material causing the diffraction. See also interferometer.

diffraction

[dĭ-frăk′shən]
  1. The bending and spreading of a wave, such as a light wave, around the edge of an object. See more at wave.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
diffraction pattern in Culture

diffraction

The breaking up of an incoming wave by some sort of geometrical structure — for example, a series of slits — followed by reconstruction of the wave by interference. Diffraction of light is characterized by alternate bands of light and dark or bands of different colors.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.