A grant (especially by a sovereign) of land (or other source of revenue) as a birthright.

"1942: they suspected that Peter II was only waiting till he had saved enough of his apanage to run away to some more civilized country. — Rebecca West, Black Lamb and Grey Falcon (Canongate 2006, p. 1046)"

A perquisite that is appropriate to one's position.

To confer an apanage upon.