bitterness vs grievance

bitterness

noun
  • The quality of feeling bitter; acrimony, resentment; the quality of exhibiting such feelings. 

  • The quality of eliciting a bitter, humiliating or harsh feeling. 

  • The quality of having a bitter taste. 

  • Harsh cold. 

grievance

noun
  • Feelings of being wronged; outrage. 

  • A formal complaint, especially in the context of a unionized workplace. 

  • A wrong or hardship suffered, which is the grounds of a complaint. 

  • Violation of regulations or objectionable behavior. 

  • A complaint or annoyance. 

  • Something which causes grief. 

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