balefire vs combustion

balefire

noun
  • An outdoor fire used in witches' rituals. 

combustion

noun
  • The act or process of burning. 

  • 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. 

  • Violent agitation, tumult. 

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