(Ὄμβριος), i. e. the rain-giver, a surname of Zeus, under which he had an altar on Mount Hymettus in Attica. (Paus. 1.32.3 ; comp. Hes. Op. et Di. 587, 620.)
[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