The Collaborative International Dictionary of English v.0.48:

Borecole \Bore"cole`\, n. [Cf. D. boerenkool (lit.) husbandman's
   cabbage.]
   A brassicaceous plant of many varieties, cultivated for its
   leaves, which are not formed into a compact head like the
   cabbage, but are loose, and are generally curled or wrinkled;
   kale.
   [1913 Webster]

WordNet (r) 3.0 (2006):

borecole
    n 1: a hardy cabbage with coarse curly leaves that do not form a
         head [syn: kale, kail, cole, borecole, colewort,
         Brassica oleracea acephala]