Īasius, ii, m., = Ἰάσιος. Son of Jupiter and Electra, beloved of Ceres, Verg. A. 3, 168; Ov. Am. 3, 10, 25.

—Called also Īasion, Ov. M. 9, 423; id. Tr. 2, 300; Hyg. F. 270; id. Astr. 2, 22.

— King of Argos and father of Atalanta, Hyg. F. 70.

— Derivv. Īasius, a, um, adj., of or belonging to Iasius, Iasian, poet. for Argive: virgo, i. e. Io, daughter of the Argive king Inachus, Val. Fl. 4, 353.

— Īasides, ae, m., a male descendant of Iasius: Palinurus, Verg. A. 5, 843; applied to Adrastus, Stat. Th. 1, 541.

— Īasis, idos, f., the daughter of Iasius, i. e. Atalanta, Prop. 1, 1, 10.