convulsion vs terrorism

convulsion

noun
  • Violent turmoil. 

  • An uncontrolled fit, as of laughter; a paroxysm. 

  • An intense, paroxysmal, involuntary muscular contraction. 

terrorism

noun
  • The use of unlawful violence against people or property to achieve political objectives. 

  • The system of fear and intimidation put into place during the Reign of Terror in Revolutionary France around 1793-94. 

  • The use of intimidation or bullying tactics. 

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