The abdomen is an anatomical area bordered on either side of the ribs and diaphragm by the lower margin, the pelvic bone (pubic ramus) below, and the flanks above. Although pain may derive from the tissues of the abdominal wall surrounding the abdominal cavity (such as skin and muscles), the term abdominal pain is widely used to describe discomfort arising from organs within the abdominal cavity. The stomach, small intestine, colon, liver, gallbladder, spleen, and pancreas are among the organs of the abdomen.