Cassiopeia (Κασσιόπεια) comes from the Greek roots kekasmai (to excel) and opos (face, voice) — meaning "she whose words excel" or "cassia juice." In Greek mythology, Cassiopeia was the vain queen of Aethiopia, placed in the sky as a constellation after her death.
Cassiopeia is rising as part of the broader return of unusual celestial and mythological names. The constellation Cassiopeia — a distinctive W-shape — is one of the most recognizable in the northern sky.
Cassiopeia does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
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In Pythagorean numerology the letters of Cassiopeia reduce to 7, The Seeker. This is a traditional interpretive system, not a factual claim about the name.