Capsicum is a genus of plants from the nightshade family (Solanaceae) native to the Americas. Some of the members of Capsicum are used as spices, vegetables, and medicines. Capsicum was cultivated for thousands of years by the people of the tropical Americas, and is now cultivated worldwide. They are commonly called chili pepper, capsicum, red or green pepper, or sweet pepper in Britain. Capsicum in Australian English and Indian English. The large mild form is called bell pepper in the US.