Sentence:  He was all bent over complaining of pains in the <WSD>abdomen</WSD>. 
Meaning of the word marked with <WSD> tags:  The cavity of the belly, which is lined by the peritoneum, and contains the viscera; often restricted in humans to the part between the diaphragm and the commencement of the pelvis, the remainder being called the pelvic cavity. (from early 17th c.)<ref name=SOED/>