Learn how to say Cassiopoeia correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word Cassiopeia:
1 Greek Mythology the wife of Cepheus, king of Ethiopia, and mother of Andromeda.
2 Astronomy a constellation near the north celestial pole, recognizable by the conspicuous ‘W’ pattern of its brightest stars.
(as genitive Cassiopeiae /ˌkasɪə(ʊ)ˈpiːʌɪ, -ˈpɪiː/) used with preceding letter or numeral to designate a star in this constellation:
the star Delta Cassiopeiae