aggression vs hostility

aggression

noun
  • The act of initiating hostilities or invasion. 

  • Hostile or destructive behavior or actions. 

  • The practice or habit of launching attacks. 

hostility

noun
  • A hostile action, especially a military action. See hostilities for specific plural definition. 

  • The state of being hostile. 

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