abdomen vs middle

abdomen

noun
  • The belly, or that part of the body between the thorax and the pelvis, not including the back; or in some lower vertebrates, the portion between the cardiac and caudal regions. 

  • The posterior section of the body, behind the thorax, in insects, crustaceans, and other Arthropoda. 

  • 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. 

middle

noun
  • The central part of a human body; the waist. 

  • A centre, midpoint. 

  • The part between the beginning and the end. 

  • The middle stump. 

  • The middle voice. 

adj
  • Pertaining to the middle voice. 

  • Located in the middle; in between. 

  • Central. 

How often have the words abdomen and middle occurred in a corpus of books? (source: Google Ngram Viewer )