The Collaborative International Dictionary of English v.0.48:

baloney \ba*lo"ney\, n.
   1. [Believed to be derived form balogna, but perhaps also
      influenced by blarney.] nonsense; foolishness; bunk; --
      also used as an interjection. [Also spelled boloney.]
      [slang]
      [PJC]

            No matter how thin you slice it, it's still baloney!
                                                  --Al Smith.
      [PJC]

   2. informal variant of bologna[2], for bologna sausage.
      [informal]
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Bologna \Bo*lo"gna\, n.
   1. A city of Italy which has given its name to various
      objects.
      [1913 Webster]

   2. A Bologna sausage; also informally called baloney.
      [1913 Webster]

   Bologna sausage [It. salsiccia di Bologna], a large sausage
      made of bacon or ham, beef, veal, and pork, cooked and
      smoked, chopped fine and inclosed in a skin.

   Bologna stone (Min.), radiated barite, or barium sulphate,
      found in roundish masses composed of radiating fibers,
      first discovered near Bologna. It is phosphorescent when
      calcined.

   Bologna vial, a vial of unannealed glass which will fly
      into pieces when its surface is scratched by a hard body,
      as by dropping into it a fragment of flint; whereas a
      bullet may be dropped into it without injury.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Bologna sausage
    n 1: large smooth-textured smoked sausage of beef and veal and
         pork [syn: bologna, Bologna sausage]