firewater vs grappa

firewater

noun
  • Water for use in firefighting. 

  • High-proof alcohol, especially whiskey (especially in the context of its sale to or consumption by Native Americans). 

  • High-temperature hydraulic condensate discharged from industrial boilers. 

grappa

noun
  • A variety or serving of grappa. 

  • An Italian grape-based spirit of between 80 and 100 proof, made from the distillation of pomace. 

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