melancholy vs sorrow

melancholy

noun
  • Great sadness or depression, especially of a thoughtful or introspective nature. 

  • Black bile, formerly thought to be one of the four "cardinal humours" of animal bodies. 

adj
  • Affected with great sadness or depression. 

sorrow

noun
  • unhappiness, woe 

  • (usually in plural) An instance or cause of unhappiness. 

verb
  • To feel grief over; to mourn, regret. 

  • To feel or express grief. 

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