Merriam-Webster Collegiate Dictionary - capsicum

 noun  Etymology: New Latin, perhaps from Latin capsa  Date: 1588  1.  a. any of a genus (Capsicum) of tropical American herbs and shrubs of the nightshade family widely cultivated for their many-seeded usually fleshy-walled berries — called also pepper  b. pepper 3b  2. an oleoresin derived from the fruit of some ~s that contains capsaicin and related compounds and is used medicinally especially as a topical pain reliever