diehard vs hardcore

diehard

adj
  • Unreasonably or stubbornly resisting change. 

  • Fanatically opposing progress or reform. 

  • Complete; having no opposite opinion of anything in a particular topic of one's values; thorough of in one's beliefs. 

noun
  • A person with such an attitude. 

hardcore

adj
  • Resistant to change. 

  • Having an extreme dedication to a certain activity. 

  • Particularly intense; thrillingly dangerous or erratic; desirably violent in appearance; pleasing or "cool" due to intensity or danger. 

  • Depicting penetration and abnormal sexual activity. 

  • Obscene or explicit. 

  • Faster or more intense than the regular style. 

noun
  • Outlaw country. 

  • Jungle. 

  • Gangsta rap. 

  • Broken bricks, stone and/or other aggregate used as foundations, especially in road and path laying. 

  • Hardcore punk. 

  • Hardcore techno. 

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