1. (astronomy) a shift in the spectra of very distant galaxies toward longer wavelengths (toward the red end of the spectrum); generally interpreted as evidence that the universe is expanding
   "The astronomer measured the redshift of the distant galaxy to estimate its velocity";
   - red shift

1. (of radiation) change frequency due to relative motion or expansion of the universe
   "Astronomers use redshifted light to measure the distance of far-off galaxies"

Derived forms: redshifted, red shifts, redshifts, redshifting

Type of: propagation

Encyclopedia: Redshift