melancholia vs sorrow

melancholia

noun
  • Deep sadness or gloom; melancholy 

  • depression, characterised by irrational fears, guilt and apathy 

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 melancholia and sorrow occurred in a corpus of books? (source: Google Ngram Viewer )