Cassiopeia

American  

[kas-ee-uh-pee-uh] / ˌkæs i əˈpi ə /

noun

genitive

Cassiopeiae

1. Astronomy. a northern constellation between Cepheus and Perseus.

2. Classical Mythology. the wife of Cepheus and mother of Andromeda.

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Cassiopeia ¹ British  

/ ˌkæsɪəˈpiːə /

noun

1. a very conspicuous W-shaped constellation near the Pole Star. Cassiopeia A is a very strong radio and X-ray source, identified as the remnant of a supernova thought to have occurred in the late 17th century

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Cassiopeia ² British  

/ ˌkæsɪəˈpiːə /

noun

1. Greek myth the wife of Cepheus and mother of Andromeda

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Cassiopeia Scientific  

/ kăs′ē-ə-pē′ə /

1. A W-shaped constellation in the Northern Hemisphere near Andromeda and Cepheus.

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Other Word Forms

• Cassiopeian adjective

Example Sentences

The star γ Cas, visible to the naked eye in the constellation Cassiopeia, has confused astronomers for decades.

From Science Daily • Mar. 25, 2026

From the ground, Apophis will resemble a star traversing the night sky, as bright as the constellation Cassiopeia and slower than a satellite.

From Los Angeles Times • Feb. 14, 2023

It's a special type of neutron star, called a magnetar, located approximately 13,000 lightyears from Earth in the constellation Cassiopeia.

From Salon • Jan. 9, 2023

SEI is working on a project called Cassiopeia, which plans to place a constellation of very large satellites in a high Earth orbit.

From BBC • Oct. 31, 2022

Cassiopeia, who was tired and cranky from the long day of travel, cupped her hands to her mouth and hissed right back.

From "The Interrupted Tale" by Maryrose Wood