The Collaborative International Dictionary of English v.0.48:

Endive \En"dive\, n. [F. endive (cf. Pr., Sp. Pg., & It.
   endivia), fr. a deriv. of L. intibus, intybus, endive.]
   (Bot.)
   A composite herb (Cichorium Endivia). Its finely divided
   and much curled leaves, when blanched, are used for salad.
   [1913 Webster]

   Wild endive (Bot.), chicory or succory.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

escarole \escarole\ n. [Fr., from OFr. scariole. fr. LL.
   escariola, L. escarius of food, fit to eat, esca food, fr.
   edere to eat.]
   a variety of endive (Cichorium endivia) often used in
   salads, having leaves with irregular frilled edges.

   Syn: endive, curly endive.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Cichorium endivia
    n 1: widely cultivated herb with leaves valued as salad green;
         either curly serrated leaves or broad flat ones that are
         usually blanched [syn: endive, witloof, Cichorium
         endivia]