Sedna is the name of a recently discovered, distant planetoid that lies in the Kuiper Belt, beyond the orbit of Neptune. While Sedna is a unique and interesting name for a celestial body, there are several synonyms that can be used to describe this object. Some alternatives to "Sedna" might include "Eris" (the name of another dwarf planet in the Kuiper Belt), "Persephone" (a reference to the Greek goddess of the underworld), or "Nemesis" (which connotes a sense of danger or retribution). Other synonyms for Sedna might include "Trans-Neptunian object", "distant planetoid", or "Kuiper Belt object". Regardless of the terminology used, Sedna remains a fascinating object to study and explore.