kohl·ra·bi 
(kōl-räbē, -răbē)
(kōl-räbē, -răbē)n. pl. kohl·ra·bies
A plant (Brassica oleracea var. gongylodes) in the mustard family, having a thick basal part of the stem that is eaten as a vegetable. Also called turnip cabbage.
[German (partial translation of Italian cavoli rape) : Kohl, cabbage (from Middle High German kōl, from Old High German, from Latin caulis) + Italian rape, pl. of rapa, turnip.]
kohlrabiBrassica oleracea var. gongylodes