refine vs sully

refine

verb
  • To purify of coarseness, vulgarity, inelegance, etc.; to polish. 

  • To improve in accuracy, delicacy, or excellence. 

  • To become pure; to be cleared of impure matter. 

  • To make nice or subtle. 

  • To purify; reduce to a fine, unmixed, or pure state; to free from impurities. 

sully

verb
  • To soil or stain; to dirty. 

  • To corrupt or damage. 

  • To become soiled or tarnished. 

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