What is Emphyteosis?

Legal Definition
Civil law. The name of a contract 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, 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 Toull. n. 144.

2. This has a striking resemblance to a ground-tent. (q. v.). See Nouveau Denisart, mot, Emphyteose; Merl. Reper. mot Emphyteose; Faber, De jure emphyt. Definit. 36; Code, 4, 66, 1.
-- Bouviers Law Dictionary