refine vs rework

refine

verb
  • To improve in accuracy, delicacy, or excellence. 

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

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

  • To make nice or subtle. 

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

rework

verb
  • To redo, correct, or rebuild. 

noun
  • Taking unsaleable food and using it in the manufacture of other food. 

  • Work done to correct defects associated with a deliverable product, plus any root cause analysis effort to identify the task(s) to be re-performed. 

  • An instance of reworking. 

  • The act of redoing, correcting, or rebuilding. 

  • Something redone, corrected or rebuilt. 

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