Andromeda was a name common to several things. Particularly confusingly, it referenced at least three quite distinct astronomical phenomena.

• Andromeda (constellation), a constellation — home to the so-called "sleepers", as well as Sabalom Glitz — which was very remote to Earth (DW: The Trial of a Time Lord)
• Andromeda (galaxy), a galaxy proximate to the Milky Way, home to the Wirrn and other species and to which humans eventually travelled. (DW: The Ark in Space and others)
• Andromeda (planet), the name of the planet on which Castrovalva was located — at least according to The Master's fictional alteration of the TARDIS Index File (DW: Castrovalva)
• Andromedan Phylox Series, the astronomical phenomenon mostly comprised of the planet of the same name
• Andromedan, the demonym for beings from the constellation of Andromeda.