Doppler shift

noun

1
: a change in frequency of an electromagnetic radiation caused by the motions of the atoms, molecules, or nuclei in the line of sight
2
: the slight displacement in the positions of the spectrum lines of light from a star or other celestial body due to the Doppler effect

Word History

Etymology

after C. J. Doppler

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Cite this Entry

“Doppler shift.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Doppler%20shift. Accessed 26 Aug. 2026.

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