Lewis & Short

Orcīnus, a, um, adj. [Orcus], of or belonging to the realms of the dead: liberti, set free by the last will of their masters, Dig. 26, 4, 3, § 3; ib. 33, 8, 22; ib. 40, 5, 30, § 12 al.: senatores, who had got into the Senate by means of Cœsar’s testament, Suet. Aug. 35.