Dioscorea alata, also known as purple yam; greater yam; Raja Ala (??? ??) is a species of yam. The tubers are usually a vivid violet-purple to bright lavender in color, but some range in color from cream to plain white.
- Common Name In Sri Lanka: Greater yam (??? ??)
- Scientific Name: Dioscorea alata
- Habitat: In tropical areas of Asia and Africa, yams occur at the edges or in the canopy gaps of rainforests and woodlands.
- Average Height: 20-30 ft
Dioscorea alata is part of the catalog of ayurvedic medicinal plants of Sri Lanka.