The Collaborative International Dictionary of English v.0.48:

Johnnycake \John"ny*cake`\ (-k[=a]k`), n.
   A kind of bread made of the meal of maize (Indian corn),
   mixed with water or milk, etc., and baked. [U.S.] --J.
   Barlow.
   [1913 Webster]

WordNet (r) 3.0 (2006):

johnnycake
    n 1: cornbread usually cooked pancake-style on a griddle
         (chiefly New England) [syn: johnnycake, johnny cake,
         journey cake]