Jatropha curcas is a species of flowering plant in the spurge family, Euphorbiaceae, that is native to the American tropics, most likely Mexico and Central America. It is originally native to the tropical areas of the Americas from Mexico to Argentina, and has been spread throughout the world in tropical and subtropical regions around the world, becoming naturalized or invasive in many areas. The specific epithet, "curcas", was first used by Portuguese doctor Garcia de Orta more than 400 years ago. Common names in English include physic nut, Barbados nut, poison nut, bubble bush or purging nut. In parts of Africa and areas in Asia such as India it is often known as "castor oil plant" or "hedge castor oil plant", but it is not the same as the usual castor oil plant, Ricinus communis (they are in the same family but different subfamilies).

J. curcas is a semi-evergreen shrub or small tree, reaching a height of 6 m (20 ft) or more. It is resistant to a high degree of aridity, allowing it to grow in deserts. It contains phorbol esters, which are considered toxic. However, edible (non-toxic) provenances native to Mexico also exist, known by the local population as piñón manso, xuta, chuta, aishte, among others.[8][9] J. curcas also contains compounds such as trypsin inhibitors, phytate, saponins and a type of lectin[10][11] known as curcin.

The seeds contain 27–40% oil[13] (average: 34.4%) that can be processed to produce a high-quality biodiesel fuel, usable in a standard diesel engine. Edible (non-toxic) varieties can be used for animal feed and food