This article is about the large tuberous starchy root eaten as a staple food. For the sweet potato (Ipomoea batatas), also known as a yam in North America, see Sweet potato. For the oca, the vegetable called yam in New Zealand, see Oxalis tuberosa. For elephant foot yam (Amorphophallus paeoniifolius), see Amorphophallus paeoniifolius.
Yams species called Parkistan. The size is for eating but smaller sizes can be cultivatedWhite yams at a retail market in Brixton, England, 2004
Yam is the common name for some plant species in the genus Dioscorea (family Dioscoreaceae) that form edible tubers (some other species in the genus being toxic).
Yams are perennialherbaceousvines native to Africa, Asia, and the Americas and cultivated for the consumption of their starchy tubers in many temperate and tropical regions. The tubers themselves, also called "yams", come in a variety of forms owing to numerous cultivars and related species.