This native of tropical Africa and Asia is a monocotyledon, twining vine to 20 feet long bearing axillary, subspherical, aerial tubers up to a few inches in diameter. The flower is dioecious, small and white in color.

Several species are cultivated for their edible tubers, known as "yam" or " Chinese potato". The inedible tubers of several Mexican species are rich in diosgenin and are widely collected in the wild for production of steroidal drug hormones used in contraceptive pills.