(Ὕπατος), the most high, occurs not only as an epithet of Zeus in poetry (Hom. Il. 8.31, 19.258), but as a real surname of the god. An altar of Zeus Hypatus existed at Athens in front of the Erechtheium; and it was not allowed to offer up to him any thing alive or libations, but only cakes. (Paus. 1.26.6, 8.2.1.) Zeus Hypatus was also worshipped at Sparta (3.17.3 ), and near Glisas in Boeotia. (9.19.3.)
[L.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890