bitterness vs mordancy

bitterness

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

  • The quality of having a bitter taste. 

  • Harsh cold. 

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

mordancy

noun
  • The state or quality of being mordant. 

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