redshift

noun

red·​shift ˈred-ˈshift 

: a displacement of the spectrum of a celestial body toward longer wavelengths that is a consequence of the Doppler effect or the gravitational field of the source

also : a measurement of a celestial body's redshift equal to the ratio of the displacement of a spectral line to its known unshifted wavelength and used especially to calculate the body's distance from earth

redshifted

ˈred-ˈshif-təd 

adjective

Examples of redshift in a Sentence

Recent Examples on the Web

Soon papers were published with claims of galaxies at redshifts of 10, 11 and even higher—and while many of those preliminary measurements wound up being spurious, several were ultimately confirmed out to redshifts greater than 14. —Phil Plait, Scientific American, 25 Dec. 2025

In that case, the redshift (z) equals zero, because the ratio of the observed wavelength to the emitted wavelength equals 1. —Big Think, 19 Nov. 2025

The image doesn't show the entirety of the Ultra Deep Field, only a section of it containing about 2,500 visible galaxies, four-fifths of them being truly distant, high redshift galaxies. —Keith Cooper, Space.com, 4 Aug. 2025

The gravitational effects of such a void add a small redshift to the light from distant objects—on top of the redshift caused by the overall expansion of the universe. —Lydia Patrick, MSNBC Newsweek, 8 July 2025

Word History

First Known Use

1923, in the meaning defined above

Rhymes for redshift

• adrift
• airlift
• facelift
• festschrift
• forklift
• gearshift
• makeshift
• sealift
• snowdrift
• spendthrift
• clift
• drift

Kids Definition

redshift

noun

red·​shift ˈred-ˈshift 

: displacement of a spectrum especially of a heavenly body toward longer wavelengths