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definitions

redshift

or red shift

[red-shift]
See more synonyms for redshift on Thesaurus.com
noun Astronomy.
  1. a shift toward longer wavelengths of the spectral lines emitted by a celestial object that is caused by the object moving away from the earth.
Compare cosmological redshift, Doppler effect, gravitational redshift.

Origin of redshift

First recorded in 1920–25; red1 + shift
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for red shift

redshift

noun
  1. a shift in the lines of the spectrum of an astronomical object towards a longer wavelength (the red end of an optical spectrum), relative to the wavelength of these lines in the terrestrial spectrum, usually as a result of the Doppler effect caused by the recession of the objectCompare: blueshift
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
red shift in Science

red shift

  1. See under Doppler effect.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
red shift in Culture

red shift

In physics, the reddening of light sent out by an object that is moving away from an observer. (See Doppler effect.)

Note

The red shift that can be observed in light from distant galaxies suggests that the universe is expanding, and thus supports the Big Bang theory.
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.