- A generally large tuberous root of one of the genus Dioscorea, with dense flesh, used as a starch staple and ranging from less than 0.5 kg to 25 kg in size. They must be cooked and are treated like potatoes. Varieties are found in all tropical and subtropical areas and a few in temperate regions. Typical are cush cush yam, Chinese yam, aerial yam, winged yam, guinea yam and Asiatic yam.
- The decorative salads of Thailand which are an art form in their own right
- The name sometimes incorrectly given to the sweet potato grown in the USA
- noun the thick tuber of a tropical plant Dioscorea