Dictionary.net

Drastic hydragogue cathartic.

The dried and powdered pulp of a kind of cucumber, much used as a purgative.

The fruit of Citrullus colocynthis: cathartic.

The fruit of Citrullus colocynthis, an annual plant of Turkey, but growing in various parts of Asia and Africa. The pulp alone is employed medicinally. Its bitter principle is colocynthin, of which it contains 14 per cent., besides extractives. Colocynth is a powerful drastic purgative and hydragogue. It enters largely into the composition of various pills and extracts, and, when modified by other ingredients, forms a very efficient and mild purgative. Colocynth is used in the form of the extract, or compound extract, usually in combination with other cathartics.

n. [Latin] The coloquintida, or bitter apple of the shops; a strong cathartic.