aperient vs defecation

aperient

noun
  • A laxative, either in the form of a medicine or a food such as asparagus or hops, which has the effect of moving the bowels, or aiding digestion and preventing constipation. 

adj
  • Having a gentle laxative effect. 

defecation

noun
  • The act or process of voiding feces from the bowels. 

  • Any of several processes for the removal of impurities, or for clarifying various materials. 

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