instability vs lycanthropy

instability

noun
  • A state that is not in equilibrium, or in which a small change has a large irreversible effect. 

  • The quality of being unstable. 

lycanthropy

noun
  • The state of being a person who can shapeshift between the form of a human being and an animal, whether or not it is a wolf. 

  • A delusion in which one believes oneself to be a wolf or other wild animal. 

  • The state of being a lycanthrope (or werewolf), a person who can shapeshift between the form of a human being and a wolf, often said to happen involuntarily during a full moon; werewolfdom. 

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