1520s, from Middle French and Old French archeduc, from Merovingian Latin archiducem (c.750); see arch- + duke (n.). Formerly the title of the rulers of Austrasia, Lorraine, Brabant, and Austria; later the titular dignity of the sons of the Emperor of Austria. Related: Archducal; archduchy.[archduke etymology, archduke origin, 英语词源]