diarrhea vs dysentery

diarrhea

noun
  • A gastrointestinal disorder characterized by frequent and very soft or watery bowel movements. 

  • The watery or very soft excrement that comes from such bowel movements. 

dysentery

noun
  • Diarrhea. 

  • A disease characterised by inflammation of the intestines, especially the colon (large intestine), accompanied by pus (white blood cells) in the feces, fever, pain in the abdomen, high-volume diarrhea, and possible blood in the feces. 

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