barong vs flamethrower

barong

noun
  • A cutting weapon similar to a cleaver, with a thick back and thin razor-like edge, used by the Moros of the Philippines. 

flamethrower

noun
  • A device that projects a flame for starting fires, and sometimes also additional fuel to help ignition. Used either as a weapon or a tool. 

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