In botany, a fruit is the ripened ovary, together with its seeds, of a flowering plant. In cuisine, when discussing fruit as food, the term usually refers to just those plant fruits that are sweet and fleshy, examples of which would be plum, apple, and orange. However, a great many common vegetables, as well as nuts and grains, are the fruit of the plants they come from. Fruits that might not be considered such in a culinary context include gourds (e.g. squash and pumpkin), maize, tomatoes, and green peppers. These are fruits to a botanist, but are generally treated as vegetables in cooking. Some spices, such as allspice and nutmeg, are fruits. Rarely, culinary "fruits" are not fruits in the botanical sense, such as rhubarb in which only the astringent stalk, or petiole, is edible.