firebomb vs incendiary

firebomb

noun
  • A weapon that causes fire; an incendiary weapon. 

verb
  • To attack with a firebomb. 

incendiary

noun
  • Something capable of causing fire, particularly a weapon. 

  • One who excites or inflames factions into quarrels. 

  • One who maliciously sets fires. 

adj
  • Intentionally stirring up strife, riot, rebellion. 

  • Capable of, or used for, or actually causing fire. 

  • Inflammatory, emotionally charged. 

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