Stomach

The stomach is a muscular, hollow, dilated part of the digestion system which functions as an important organ of the digestive tract in some animals, including vertebrates, echinoderms, insects (mid-gut), and molluscs. It is involved in the second phase of digestion, following mastication (chewing).
The stomach is located between the esophagus and the small intestine. It secretes protein-digesting enzymes and strong acids to aid in food digestion, (sent to it via oesophageal peristalsis) through smooth muscular contortions (called segmentation) before sending partially digested food (chyme) to the small intestines.

Ascites

Ascites is the accumulation of fluid (usually serous fluid which is a pale yellow and clear fluid) in the abdominal (peritoneal) cavity. The abdominal cavity is located below the chest cavity, separated from it by the diaphragm. Ascitic fluid can have many sources such as liver disease, cancers, congestive heart failure, or kidney failure. A person with ascites usually has severe liver disease. Ascites due to liver disease is caused by high pressure in the blood vessels of the liver (portal hypertension) and low albumin levels.