Cepheid

noun

Ce·​phe·​id ˈse-f(ē-)id How to pronounce Cepheid (audio) ˈsē- How to pronounce Cepheid (audio)
: any of a class of variable stars whose very regular light variations are related directly to their intrinsic luminosities and whose apparent luminosities are used to estimate distances in astronomy

Word History

Etymology

International Scientific Vocabulary, from Cepheus

First Known Use

circa 1903, in the meaning defined above

Time Traveler
The first known use of Cepheid was circa 1903

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Cite this Entry

“Cepheid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Cepheid. Accessed 9 Sep. 2025.

Kids Definition

Cepheid

noun
Ce·​phe·​id ˈsē-fē-əd How to pronounce Cepheid (audio)
: one of a class of pulsating stars whose changes in brightness are very regular
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