 Eris is named after the Greek goddess "Eris" (Greek ), a personification of strife and discord.The name was proposed by the Caltech Team on September 6, 2006, and it was assigned on September 13, 2006, following an unusually long period in which the object was known by the provisional designation , which was granted automatically by the IAU under their naming protocols for minor planets.Like the moons Io and Mimas, and for the same reason, the name "Eris" has two competing pronunciations, with a 'long' and a 'short' "e".