Turpeth

Part of speech: noun (n.)

1. The root of Ipomoea Turpethum, a plant of Ceylon, Malabar, and Australia, formerly used in medicine as a purgative; -- sometimes called vegetable turpeth.

2. A heavy yellow powder, Hg3O2SO4, which consists of a basic mercuric sulphate; -- called also turpeth mineral.