{ , a. [ L. hypaethrus in the open air, uncovered, Gr. &unr_;; &unr_; under + &unr_; ether, the clear sky. ] (Arch.) Exposed to the air; wanting a roof; -- applied to a building or part of a building. Gwilt. [ 1913 Webster ]
n. [ NL. turpethum, fr. Per. tirbid a cathartic, turbad a purgative root. Cf. Turbith. ] [ Written also turbeth, and turbith. ]1. (Bot.) The root of Ipomœa Turpethum, a plant of Ceylon, Malabar, and Australia, formerly used in medicine as a purgative; -- sometimes called vegetable turpeth. [ 1913 Webster ]
2. (Chem.) A heavy yellow powder, Hg3O2SO4, which consists of a basic mercuric sulphate; -- called also turpeth mineral. [ 1913 Webster ]