The winter melon, also called white gourd, winter gourd, or ash gourd, is a vine grown for its very large fruit, eaten as a vegetable when mature. It is the only member of the genus Benincasa. The fruit is fuzzy when young. The immature melon has thick white flesh that is sweet when eaten. By maturity, the fruit loses its hairs and develops a waxy coating, giving rise to the name wax gourd, and providing a long shelf life. The melon may grow as large as 80 cm in length. Although the fruit is referred to as a "melon," the fully grown crop is not sweet. Originally cultivated in Southeast Asia, the winter melon is now widely grown in East Asia and South Asia as well.
Winter melon is also a common name for members of the Inodorus cultivar group of the muskmelon (Cucumis melo L), more commonly known as casaba or honeydew melons.