Lewis & Short

2. Īō, Iūs, and Īōn, Iōnis, f., = Ἰώ, a daughter of Inachus, king of Argos, beloved by Jupiter, and changed, through fear of Juno, into a cow; afterwards worshipped as an Egyptian deity, under the name of Isis.
Form Io, Ov. H. 14, 85; Prop. 2, 28 (3, 24), 17; Ov. M. 1, 588 sq.; Val. Fl. 4, 351 sq.; Hyg. Fab. 145.
Gen. Ius, Nemes. Cyn. 31.
Acc. Io, Ov. M. 1, 588; Amm. 2, 19, 29.
Abl. Io, Prop. 2, 13, 19.
Form Ion; dat. Ioni, Plaut. Aul. 3, 6, 20.
Acc. Ionem, Serv. Verg. A. 3, 153.

1. ĭon, ĭi, n. [ἴον].

  1. I. A kind of violet, Plin. 21, 11, 38, § 64; plur.: ia, id. 21, 6, 14, § 27.
  2. II. A precious stone of a violet color, Plin. 37, 10, 61, § 170.

2. Īon, ōnis, m., = Ἴων,

  1. I. an Athenian, son of Xuthus, who led a colony into Asia; from him is derived the name Ionia, Vitr. 4, 1; Stat. Th. 8, 454.
  2. II. A sculptor of the one hundred and thirteenth Olympiad, Plin. 34, 8, 19, § 51.