contagious vs epidemic

contagious

adj
  • Having a disease that can be transmitted to another person. 

  • Easily transmitted to others. 

  • Easily passed on to others. 

epidemic

adj
  • Like or having to do with an epidemic; widespread. 

noun
  • An occurrence of a disease or disorder in a population at a frequency higher than that expected in a given time period; an episode of outbreak and subsequent high prevalence. 

  • A widespread disease that affects many individuals in a population. 

  • The spreading of an idea or belief amongst a population. 

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