begrime vs blacken

begrime

verb
  • To ingrain grime or dirt which is difficult to remove into (something); also (more generally), to make (something) dirty; to soil. 

blacken

verb
  • To make dirty. 

  • To defame or sully. 

  • To cook (meat or fish) by coating with pepper, etc., and quickly searing in a hot pan. 

  • To become black. 

  • To cause to be or become black. 

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