The Collaborative International Dictionary of English v.0.48:

Bouillon \Bou`illon"\, n. [F., fr. bouillir to boil.]
   1. A nutritious liquid food made by boiling beef, or other
      meat, in water; a clear soup or broth.
      [1913 Webster]

   2. (Far.) An excrescence on a horse's frush or frog.
      [1913 Webster]

WordNet (r) 3.0 (2006):

bouillon
    n 1: a clear seasoned broth

Moby Thesaurus II by Grady Ward, 1.0:

52 Moby Thesaurus words for "bouillon":
   beef, beef extract, beef tea, bisque, borscht, bouillabaisse,
   broth, bully, bully beef, burgoo, charqui, chicken soup,
   chipped beef, chowder, clam chowder, clear soup, consomme,
   dried beef, egg drop soup, fish soup, gazpacho, gravy soup,
   ground beef, gumbo, hamburger, jerky, julienne, matzo ball soup,
   minestrone, misoshiru soup, mock turtle soup, mulligatawny,
   oxtail soup, pastrami, pot-au-feu, potage, potage au tomate,
   potato soup, pottage, puree, roast beef, salt beef, soup, stock,
   suet, thick soup, thin soup, tomato soup, turtle soup,
   vegetable soup, vichyssoise, won ton soup