blacken vs elt

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. 

elt

verb
  • To begrime; soil with mud; daub; smear. 

  • To knead dough; stir dough previously kneaded to a proper consistency before baking. 

  • To meddle; interfere. 

  • To work persistently or laboriously; be occupied in working (e.g. in the earth, rake among dirt, etc.). 

  • To become soft; become moist, as damp earth. 

  • To injure (anything) by rough handling; handle roughly. 

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