Cepheid variable

American  

Or cepheid variable

noun

Astronomy.

1. a variable star in which changes in brightness are due to alternate contractions and expansions in volume.

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Cepheid variable British  

/ ˈsiːfɪɪd /

noun

1. astronomy any of a class of variable stars with regular cycles of variations in luminosity (most ranging from three to fifty days). There is a relationship between the periods of variation and the absolute magnitudes, which is used for measuring the distance of such stars

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Etymology

Origin of Cepheid variable

First recorded in 1900–05; Cephe(us) + -id ¹

Example Sentences

These include Cepheid variable stars, which brighten and dim in predictable ways, red giant stars with known brightness, Type Ia supernovae, and certain galaxy types.

From Science Daily • Apr. 12, 2026

These ladders are built from objects such as supernovae and special stars called Cepheid variable stars.

From Science Daily • Dec. 9, 2025

It was a Cepheid variable, a type of star beloved by astronomers because its luminosity and pulse length can be used to measure its distance from Earth.

From Los Angeles Times • Oct. 3, 2023

First observed in 1784, Cepheid variable stars are stars whose brightness varies over some regular period.

From Scientific American • Feb. 10, 2012

A special type of star, called a Cepheid variable, had a property that allowed Hubble to measure the distance to faraway objects.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife