Kohlrabi, also called German turnip or turnip cabbage, is a biennial vegetable, a low, stout cultivar of wild cabbage. It is a cultivar of the same species as cabbage, broccoli, cauliflower, kale, Brussels sprouts, collard greens, Savoy cabbage, and gai lan.

Brassica oleracea is a plant species from family Brassicaceae that includes many common cultivars used as vegetables, such as cabbage, broccoli, cauliflower, kale, Brussels sprouts, collard greens, Savoy cabbage, kohlrabi, and gai lan.