Chow chow, or chayote squash (Sechium edule), is a pale green, pear-shaped, mild-flavored, and crisp vegetable from the gourd family (Cucurbitaceae). Often used in stews, salads, and South Indian curries (koottu), it is low in calories, fat-free, and high in fiber and folate, making it a popular choice for healthy, hydrating diets.