extrinsic vs primal

extrinsic

adj
  • external; separable from the thing itself; inessential 

  • not belonging to something; outside 

noun
  • An external factor 

primal

verb
  • To take part in primal therapy. 

noun
  • A primal cut (of meat). 

adj
  • Being the first in time or in history. 

  • Of greatest importance; primary. 

  • Being one of the pieces of meat initially separated from the carcass during butchering, prior to division into smaller cuts. 

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