consumable vs usable

consumable

adj
  • That is consumed or depleted upon use. 

  • That may be eaten. 

noun
  • A material or product that is produced for consumption. 

usable

adj
  • Capable of being used. 

  • Easy to use; exhibiting good usability. 

  • homosexual 

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