Japanese mountain yam

English Noun A Japanese species of yam, Dioscorea japonica species Another species of yam, Dioscorea polystachya species, which is sometimes referred to as a mountain yam in China. Usage notes There is a great deal of confusion about names for yams, even in very good references. Dioscorea japonica species probably has the best etymological claim to the name, but usage is abundant for both. Synonyms Dioscorea japonica en yamaimo en Dioscoreales order plants Root vegetables