- Proper noun. (Greek mythology) The daughter of Cepheus and Cassiopeia, king and queen of Eritrea, rescued from her sacrifice to a sea monster by Perseus who married her; mother of Perseus, ancient king of Persia.
- Proper noun. (constellation) An autumn constellation of the northern sky representing the "Chained Lady" Andromeda from Greek myth. The constellation lies between Pisces and Cassiopeia.
- Proper noun. (galaxy) Andromeda Galaxy, the nearest spiral galaxy to the Milky Way; M31.