Merriam-Webster Collegiate Dictionary - jalap

 noun  Etymology: French & Spanish; French ~, from Spanish ~a, from Jalapa, Mexico  Date: 1644  1.  a. the dried tuberous root of a Mexican plant (Ipomoea purga syn. Exogonium purga) of the morning-glory family; also a powdered purgative drug prepared from it that contains resinous glycosides  b. the root or derived drug of plants related to the one supplying ~  2. a plant yielding ~