leper vs leprosity

leper

noun
  • Synonym of outcast: A person who is shunned, a pariah. 

  • A person who has leprosy, a person suffering from Hansen's disease. 

leprosity

noun
  • The supposed impurity or impurities of various metals, understood as causing their deviation from gold. 

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