dejection vs heartache

dejection

noun
  • The act of humbling or abasing oneself. 

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

  • A low condition; weakness; inability. 

heartache

noun
  • Very sincere and difficult emotional problems or stress. 

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