Peritonitis

n. inflammation of the peritoneum, inflammation of the membrane that lines the abdominal cavity (Medicine)

This article is concerned with peritonitis in human beings. For a specific cause of peritonitis in cats, see feline infectious peritonitis. Peritonitis is defined as inflammation of the peritoneum (the serous membrane which lines part of the abdominal cavity and some of the viscera it contains). It may be localised or generalised, generally has an acute course, and may depend on either infection (often due to rupture of a hollow viscus) or on a non-infectious process. Peritonitis generally represents a surgical emergency.
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n. peritonitis, inflammation of the peritoneum, inflammation of the membrane that lines the abdominal cavity (Medicine)

(n.)
Inflammation of the peritoneum.
  

Inflammation of the peritoneum (The peritoneum is the tissue layer of cells lining the inner wall of the abdomen and pelvis). Peritonitis can result from infection (such as bacteria or parasites), injury and bleeding, or diseases (such as systemic lupus erythematosus).