Butternut squash (Cucurbita moschata), known in Australia and New Zealand as butternut pumpkin or gramma, is a type of winter squash that grows on a vine. It has a sweet, nutty taste similar to that of a pumpkin. It has tan-yellow skin and orange fleshy pulp with a compartment of seeds in the blossom end. When ripe, it turns increasingly deep orange, and becomes sweeter and richer. It is a good source of fiber, vitamin C, magnesium, and potassium; and it is a source of vitamin A.
Although botanically a fruit, butternut squash is used culinarily as a vegetable that can be roasted, sautéed, toasted, puréed for soups such as squash soup, or mashed to be used in casseroles, breads, muffins, and pies. The squash is also used as an alternative diet for Monarch butterfly caterpillars alongside cucumbers. It is part of the same squash family as ponca, waltham, pumpkin, and calabaza.