Utah State University Extension
The term squash is used for several different members of the "cucurbita" family which includes the squash, pumpkin and gourds all of which are native to the western hemisphere. Today the term squash is used for several quite different members of the family, which are divided roughly into summer and winter squashes.
USU, "Zucchini - The Chameleon of the Squash World" (2005). All Current Publications. Paper 1094.