jalapEnglishOxford Dictionary of Englishjalap /ˈdʒaləp , ˈdʒɒləp / ▸ noun [mass noun] a purgative drug obtained chiefly from the tuberous roots of a Mexican climbing plant. This drug is obtained from Ipomoea purga, family Convolvulaceae. – ORIGIN mid 17th century: from French, from Spanish ( purga de) Jalapa (see Jalapa).