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


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

Dictionary Entries Near Cepheid

Cite this Entry

“Cepheid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Cepheid. Accessed 30 Jan. 2023.

Kids Definition


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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