In Greek mythology, Tereis was one of the names given for the slave who was the mother, by Menelaus, of Megapenthes.
[1] According to R. L. Fowler, the name Tereis occurs nowhere else, may be associated with Thrace, and is possibly corrupt.
[2] Homer's Odyssey, and the geographer Pausanias, mention that Megapenthes was the illegitimate son of Menelaus, king of Mycenaean Sparta, by a slave, without naming her.
[3] But according to one source, the sixth-century BC mythographer Acusilaus (as reported by the mythographer Apollodorus), the name of the slave was Tereis.
[4] Other sources give other names for the slave who bore Megapenthes.