Yes, my learned friend, it is! And here is why:
Prince of Orange is a title of nobility, originally associated with the principality of Orange in southern France. It may be carried by members of the House of Orange-Nassau and the House of Hohenzollern, and is currently carried by Prince Willem-Alexander of the Netherlands (Orange-Nassau) and Prince Georg Friedrich of Prussia (Hohenzollern).
The title originally referred to the sovereign principality of Orange in the valley of Rhone in southern France, which was a property of the House of Orange (and from 1544 of the House of Orange-Nassau). Because Orange was a fief in the Holy Roman Empire, in its Kingdom of Burgundy, the title contained feudal rights and that sovereignty which German principalities came to enjoy. The last descendant of original princes, René of Nassau, left the principality to his cousin William the Silent, who was not of the descent of original Orange family. In 1673, Louis XIV of France annexed all territory of the principality as part of the war actions against the Stadtholder William III of Orange (d.1702 - who later became king William III of England and Scotland).
Because William III died without legitimate children, the principality was regarded as having been inherited by his closest cognatic relative, Frederick of Prussia, who ceded the principality (at least the lands, but not formally the title) to France in 1713 (France supported his claim, of course). In this way the territory of the principality lost its feudal and secular privileges and became a part of France. The title remains in the Hohenzollern royal family (who reigned in Prussia until 1918) and could be used even today by them; it was also bestowed by the French king upon Louis de Mailly, whose family still holds the title today.
An agnatic relative of William III, John Willem Friso of Nassau, who also by female line descended from William the Silent, was designated the heir to the princes of Orange in the Netherlands, by the last will of William III, and several of his descendants became Stadtholders. They claimed the principality of Orange on the basis of agnatic inheritance (similar to that of William the Silent inheriting from his cousin René, though not being a descendant of original princes of Orange), and also on basis of the testament of William III. France never allowed them to obtain anything of the principality itself (located in southern France), but they nevertheless assumed the title. From that derivation of the title comes the tradition of later Stadtholders of the Netherlands, and the present-day royal family of the Netherlands, also holding this title.
William the Silent, first Stadtholder of the United Provinces (better known as the Dutch Republic) was the most significant representative of the House of Orange within the Netherlands. He, originally a count of a small German county, portion of Nassau and heir of his father's some fiefs in Holland, obtained more extensive lands in the Netherlands (lordship of Breda and several other dependencies) as an inheritance from his cousin René, Prince of Orange, when 11 years old. After William's assassination in 1584, the title and position passed down firstly to his son Philip (who was Catholic and was imprisoned for a long time), then to second son Maurice, who later passed it on to the youngest brother, Frederick Henry.
The title of Prince of Orange became soon practically synonymous with the Stadtholder of the Netherlands.
William III was also King of Great Britain and Ireland and his legacy is commemorated annually by the Protestant Orange Order.