The chili pepper (also chile pepper or chilli pepper, from Nahuatl chīlli [ˈt͡ʃiːli]) is the fruit of plants from the genus Capsicum, members of the nightshade family, Solanaceae.[1] In Britain, Australia, Ireland, New Zealand, South Africa, Pakistan, India,[2] and other Asian countries, it is usually known simply as the chilli.

The substances that give chili peppers their intensity when ingested or applied topically are capsaicin and several related chemicals, collectively called capsaicinoids.