Turbith, or Turpeth, an officinal drug, being the bark from the fleshy roots of the Convolvulus Turpethum, L. an exotic species of the Bind-weed, growing in Ceylon.

Turbith is imported in oblong pieces, which are of a brown, or ash-colour externally, and whitish within. The best is brittle ; contains a large portion of resinous matter ; and is at first of a sweetish taste ; but, when chewed, it becomes pungent and nauseous. - This drug is occasionally employed as a purgative ; but is by no means safe, or uniform, in its operation. - It pays, when imported by the East-India Company, 2l. per ant. according to its value, and farther, Is 1 1/2d. per lb. being the duty for home consumption.