Chocolate: A food or flavoring made from the seeds of the cacao or chocolate tree. Chocolate is rich in flavinoids, compounds that act as antioxidants. Flavinoids may also lower blood pressure and improve blood flow, by regulating the synthesis of nitric oxide, which dilates blood vessels. Flavinoids, like aspirin, help keep platelets from aggregating on vessel walls. Thus, chocolate may have health benefits, provided it is consumed in moderation.