midriff
     n 1: the middle area of the human torso (usually in front);
          "young American women believe that a bare midriff is
          fashionable" [syn: {middle}, {midsection}]
     2: (anatomy) a muscular partition separating the abdominal and
        thoracic cavities; functions in respiration [syn: {diaphragm}]
Source: WordNet® 2.0