inertia vs phlegm

inertia

noun
  • In a person, unwillingness to take action. 

  • Lack of activity; sluggishness; said especially of the uterus, when, in labour, its contractions have nearly or wholly ceased. 

  • The property of a body that resists any change to its uniform motion; equivalent to its mass. 

phlegm

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

  • 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. 

  • 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 inertia and phlegm occurred in a corpus of books? (source: Google Ngram Viewer )