mercurialness vs phlegm

mercurialness

noun
  • Quality of being mercurial; mercuriality. 

phlegm

noun
  • One of the four humors making up the body in ancient and mediaeval medicine; said to be cold and moist, and often identified with mucus. 

  • Calmness of temperament, composure; also seen negatively, sluggishness, indifference. 

  • Viscid mucus produced by the body, later especially mucus expelled from the bronchial passages by coughing. 

  • A watery distillation, especially one obtained from plant matter; an aqueous solution. 

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