diarrhea vs excretion

diarrhea

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

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

excretion

noun
  • Something excreted in that manner, especially urine or feces. 

  • The process of removing or ejecting material that has no further utility, especially from the body; the act of excreting. 

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