dejection vs melancholia

dejection

noun
  • A state of melancholy or depression; low spirits, the blues. 

  • The act of humbling or abasing oneself. 

  • A low condition; weakness; inability. 

melancholia

noun
  • Deep sadness or gloom; melancholy 

  • depression, characterised by irrational fears, guilt and apathy 

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