The Collaborative International Dictionary of English v.0.48:

Everglade \Ev`er*glade\, n.
   A swamp or low tract of land inundated with water and
   interspersed with hummocks, or small islands, and patches of
   high grass; as, the everglades of Florida. [U. S.]
   [1913 Webster]

   Note: When used in the United States without qualification,
         the word Everglades is understood to refer to the
         Everglades of southern Florida.
         [PJC]

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "everglade":
   baygall, bog, bottom, bottomland, bottoms, buffalo wallow, fen,
   fenland, glade, hog wallow, holm, marais, marish, marsh, marshland,
   meadow, mere, mire, moor, moorland, morass, moss, mud, mud flat,
   peat bog, quagmire, quicksand, salt marsh, slob land, slough,
   sough, sump, swale, swamp, swampland, taiga, wallow, wash