Purple yam is a species of yam. In botany, this species is also known by the names "water yam" and "winged yam." It contains pigments that gives its bright lavender color. It is sometimes confused with taro and the Okinawa sweet potato (Ipomoea batatas cv. Ayamurasaki). In Hawaiʻi it is known as uhi, in India as ratalu or violet yam, in Marathi as KondFal (कोंदफळ), in the Philippines as ube, in Tamil as "Rasa Valli Kilangu", in Tonga, Samoa and Tahiti as ʻufi" , and in Vietnam as khoai mỡ.