n.
Pronunciation: ' red- ' shift
Function: noun
Date: 1923
: 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
– red · shift · ed adjective