a king of Mycenae, son of Pelops, father of Agamemnon and Menelaus, and member of the family known as the Atreids (ˈeɪtrɪɪdz)
Atreus in American English
(ˈeɪtriəs)
noun
Greek Mythology
a king of Mycenae and father of Agamemnon and Menelaus: to avenge the treachery of his brother, Thyestes, he kills Thyestes' sons and serves their flesh to him at a banquet