Source : Webster's Revised Unabridged Dictionary (1913)

Colewort \Cole"wort`\, n. [AS. cawlwyrt; cawl cole + wyrt wort.
   Cf. {Collards}.]
   1. A variety of cabbage in which the leaves never form a
      compact head.

   2. Any white cabbage before the head has become firm.

Source : WordNet®

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