marketable vs merchantable

marketable

adj
  • Of or pertaining to marketability; capable of being marketed. 

  • saleable (of goods) or employable (of people) 

merchantable

adj
  • Fit for the market, i.e. suitable for selling for an ordinary price. Sometimes, this is a technical designation for a particular kind or class. 

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