horseradish tree

1 :  an East Indian tree (Moringa oleifera) that has a horseradish-flavored root and is cultivated throughout the tropics for its elongated capsular fruit which when young is pickled or cooked as a vegetable and for its seeds which yield ben oil

2 :  any Australian tree of the genus Codonocarpus (family Phytolaccaceae) having pungent leaves suggesting the flavor of horseradish or mustard