 The term "pumpkin" has no agreed upon botanical or scientific meaning, and is used interchangeably with "squash" and "winter squash".In North America and the United Kingdom, "pumpkin" traditionally refers to only certain round orange varieties of winter squash, predominantly derived from "Cucurbita pepo", while in New Zealand and Australian English, the term "pumpkin" generally refers to all winter squash.Pumpkins, like other squash, originated in northeastern Mexico and southern United States.