http://en.wikipedia.org/wiki/Chios_(mythology)
In Greek mythology, Chios was the eponym of the island of Chios. He was the son of Poseidon and an unnamed nymph, and received his name from the heavy snowfall that occurred while his mother was in labour (cf. Ancient Greek χιών chiōn "snow").<1>
Other ancient sources mention a different Chios, son or daughter of Oceanus, as an alternate eponym for the island, and also state that it could as well have taken its name from the nymph Chione, or simply from the snowy weather.<2><3>
1.^ Pausanias, Description of Greece, 7. 4. 8
2.^ Stephanus of Byzantium, s. v. Khios
3.^ Pliny the Elder, Naturalis Historia, 5. 38