burnable vs flammable

burnable

adj
  • Able to be burned; combustible 

noun
  • Anything that can be burned. 

flammable

adj
  • Capable of burning, especially a liquid. 

  • Subject to easy ignition and rapid flaming combustion. 

  • Easily set on fire. 

noun
  • Any flammable substance. 

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