combustion vs explosion

combustion

noun
  • Violent agitation, tumult. 

  • A process wherein a fuel is combined with oxygen, usually at high temperature, releasing heat. 

  • A process whereby two chemicals are combined to produce heat. 

  • The act or process of burning. 

explosion

noun
  • A sudden outburst. 

  • A sudden uncontrolled increase. 

  • A violent release of energy (sometimes mechanical, nuclear, or chemical.) 

  • A bursting due to pressure. 

  • The sound of an explosion. 

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