Ricinus communis, the castor bean  or castor oil plant  is a species of perennial flowering plant in the spurge family, Euphorbiaceae. It is the sole species in the monotypic genus, Ricinus, and subtribe, Ricininae. The evolution of castor and its relation to other species are currently being studied using modern genetic tools.

Castor is a plant that produces seeds (beans). Castor oil is produced from ripe seeds that have had their outer covering (hull) removed. Castor oil has been used as a medicine for centuries.

Castor oil is used for constipation and bowel preparation prior to colonoscopy, childbirth, and many other conditions, but there is no good scientific evidence to support these uses.

The hull of the castor seed contains a deadly poison called ricin. This is why the hull must be removed before use. Ricin has been tested as a chemical warfare agent. Weapons-grade ricin is purified and produced in particles that are so small they can be breathed in.

How does it work ?
Castor bean is used to make castor oil, which is a strong laxative. In pregnancy, castor oil might start labor by stimulating the uterus.