[ noun ] any property (real or personal or mixed) that can be inherited <noun.possession>
Hereditament \Her`e*dit"a*ment\, n. [LL. hereditamentum. See {Hereditable}.] (Law) Any species of property that may be inherited; lands, tenements, anything corporeal or incorporeal, real, personal, or mixed, that may descend to an heir. --Blackstone.
Note: A corporeal hereditament is visible and tangible; an incorporeal hereditament is not in itself visible or tangible, being an hereditary right, interest, or obligation, as duty to pay rent, or a right of way.
It is essentially a completely empty title: technically, an "incorporeal hereditament."