A pumpkin is the round, ribbed, thick-shelled fruit of certain Cucurbita vines — typically orange, but also white, green, blue-grey or buff — grown for its dense, sweet flesh, its hull-less or shelled seeds, and, in autumn, for carving. Mild and squash-green raw, it turns sweet, nutty and caramelly when roasted, baked or simmered into soup and pie.