It seems that יוון originates from "Ion". It's pretty interesting that the Turks have their name for Greece from exactly the same source (Yunanistan).
Btw, this word written looks awesome :D
Indeed, Greece is called according to the first type of Greek with whom the language speakers had contact: The Graecii for the Romans, and the Ionians for most middle easterners. This makes me wonder: Does anyone call them by their native name? And does another country call them Dorians, or Eolians?