Appenage

An appanage or apanage (pronounced /ˈæpənɪdʒ/) or French: apanage (French pronunciation: ​[a.pa.naʒ]) is the grant of an estate, title, office, or other thing of value to a younger male 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.

Late Latin *appanaticum, from appanare or adpanare 'to give bread' (panis), a pars pro toto for food and other necessities, hence for a "subsistence" income, notably in kind, as from assigned land.

An appanage was a concession of a fief by the sovereign to his younger sons, while the eldest son became king on the death of his father. Appanages were considered as part of the inheritance transmitted to the puisne (French puis, "later", + né, "born [masc.]") sons; the word Juveigneur (from the Latin comparative iuvenior, 'younger [masc.]'; in Brittany's customary law only the youngest brother) was specifically used for the royal princes holding an appanage. These lands could not be sold, neither hypothetically nor as a dowry, and returned to the royal domain on the extinction of the princely line. Daughters were excluded from the system: Salic law then generally prohibited daughters from inheriting land and also from acceding to the throne.

...
Wikipedia