Try Our Apps


Avoid these words. Seriously.


or red shift

[red-shift] /ˈrɛdˌʃɪft/
noun, Astronomy.
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.
Origin of redshift
First recorded in 1920-25; red1 + shift Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
Cite This Source
British Dictionary definitions for red shift


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 object Compare 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
Cite This Source
Contemporary definitions for red shift

in astronomy, an increase in the wavelength of radiation emitted by astronomical objects, causing a shift of features in their spectra towards longer wavelengths due to their recession from the observer

Usage Note

science's 21st Century Lexicon
Copyright © 2003-2014, LLC
Cite This Source
red shift in Science
red shift  
See under Doppler effect.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
red shift in Culture

red shift definition

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 Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source

Word of the Day

Nearby words for red shift

Difficulty index for redshift

Few English speakers likely know this word

Word Value for red

Scrabble Words With Friends