apanage

An appanage, or apanage (/ˈæpənɪdʒ/; French: apanage [a.pa.naʒ]), is the grant of an estate, title, office or other thing of value to a younger child of a sovereign, who would otherwise have no inheritance under the system of primogeniture. It was common in much of Europe. The system of appanage greatly influenced the territorial construction of France and the German states and explains why many of the former provinces of France had coats of arms which were modified versions of the king's arms. https://en.wikipedia.org/wiki/Appanage