Possessio civilis

In Roman law. A legal possession i. e., a possessing accompanied with the intention to be or to thereby become owner; and, as so understood, it was distinguished from "possessio naturalis," otherwise called "nuda detentio," which was a possessing without any such intention. Possessio dvilis was the basis of usucapio or of longi temporis possessio, and was usually (but not necessarily) adverse possession.

Brown.