Emphyteusis

In Civil Law. The name of a contract, in the nature of a perpetual lease, by which the owner of an uncultivated piece of land granted it to another, either in perpetuity or for a long time, on condition that he should improve it, by building on, planting, or cultivating it, and should pay for it an annual rent, with a right to the grantee to alienate it, or transmit it by descent to his heirs, and under a condition that the grantor should never re-enter as long as the rent should be paid to him by the grantee or his assigns.

Inst 3, 25, 3; 18 Toullier, n. 144.