This is from the New Shorter Oxford (English monolingual):
Any of several plants grown in the Carribbean and in Central and South America for their edible tubers

Malanga is a root vegetable popular in the tropics and South America. In Florida, malanga is the most popular form of cocoyam, which is a general name applied to several species of Xanthosoma. It is also called yautia, cocoyam, eddo, coco, tannia, sato-imo, and Japanese potatoes. Leafy species of Xanthosoma not grown for tubers are called belembe and calalous. There are actually two different malangas: Malanga blanca (Xantyosoma sagittifikium), considered the true malanga, which grows on dry land. The other is malanga amarillo (Colocasia esculenta) which grows in wet bog-like areas.

Generally, malanga resembles dasheen (taro) and the elephant-ear plant with large green leaves about 2 feet wide by 2 1/2 feet long. The malanga plant may attain a height of 5 feet or more. Edible tubers (cormels) are formed in the soil at the base of the plant. A central large tuber (corm) is formed, with a cluster of cormels, grayish brown to black lateral tubers, around it. Malanga are about the size and shape of a regular white potato; they look a little like an overgrown gladiola bulb, because the outside skin of the malanga is brown and somewhat hairy. It generally weighs 1/2 to 2 pounds, but can be heavier. The interior has an extremely crisp texture and can vary in color from cream, yellow or pink.

Glosario Internacional para el traductor, Marina Orellana.