metis vs of color

metis

adj
  • Of mixed heritage 

  • Of Métis heritage. 

noun
  • A person of mixed-race ancestry. 

  • A person of one-eighth black ancestry; an octoroon. 

  • Practical intelligence; street smarts. 

of color

adj
  • Belonging to a category of people with mixed black and white ancestry in the Americas in the 18th and early 19th centuries. 

  • Nonwhite; of a race other than white, for example black. 

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