The Collaborative International Dictionary of English v.0.48:

Gumbo \Gum"bo\ (g[u^]m"b[-o]), n. [Written also gombo.]
   1. A soup thickened with the mucilaginous pods of the okra;
      okra soup. Especially, A thick stew made with chicken
      (chicken gumbo), or seafood (seafood gumbo), thickened
      with okra or file, and also containing greens and often
      hot spices; it is particularly popular in Louisiana.
      [1913 Webster]

   2. The okra plant or its pods.
      [1913 Webster]