salivation vs sputum

salivation

noun
  • The process of producing saliva; drooling. 

sputum

noun
  • Matter coughed up and expectorated from the mouth, composed of saliva and discharges from the respiratory passages such as mucus, phlegm or pus. 

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