A pumpkin is a gourd-like squash of the genus Cucurbita and the family Cucurbitaceae (which also includes gourds). It commonly refers to cultivars of any one of the species Cucurbita pepo, Cucurbita mixta, Cucurbita maxima, and Cucurbita moschata, and is native to North America. They typically have a thick, orange or yellow shell, creased from the stem to the bottom, containing the seeds and pulp. Pumpkins are widely grown for commercial use, and are used both in food and recreation. Pumpkin pie, for instance, is a traditional part of Thanksgiving meals in the United States, and pumpkins are frequently carved as decorations around Halloween. A pumpkin that has a little face carved in it and hollowed out and decorated with candles inside is known as a jack o'lantern; these are often used at Hallowe'en, for example, to decorate windows.

In Australian English, the name 'pumpkin' generally refers to the broader category called winter squash in North America.