redshift

American  

[red-shift] / ˈrɛdˌʃɪft /

Or red shift

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.

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redshift British  

/ ˈredˌʃɪft /

noun

1. Compare: blueshift.  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

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Etymology

Origin of redshift

First recorded in 1920–25; red ¹ + shift

Compare meaning

How does redshift compare to similar and commonly confused words? Explore the most common comparisons:

• redshift vs. blueshift

Example Sentences

See Examples For:

redshift

The galaxy sits at redshift 2, meaning astronomers see it as it appeared roughly 3.3 billion years after the Big Bang.

From Science Daily ● Aug. 17, 2026

The researchers are now aiming to discover the first known quasar beyond a redshift of 8, which would reveal an object that existed within the universe's first 630 million years.

From Science Daily ● Jul. 9, 2026

According to the researchers, the new method delivers redshift estimates with precision comparable to spectroscopic measurements, but without requiring spectra.

From Science Daily ● Jun. 29, 2026

In essence, Ivanov said, "It's the highest redshift, spectroscopically confirmed, unlensed barred spiral galaxy."

From Science Daily ● Feb. 27, 2026

Due to the expansion of the universe, that wavelength was stretched to nearly five times its original value, placing it in the near-infrared, a process called cosmological redshift.

From Science Daily ● Nov. 29, 2025