bitter pill vs mischance

bitter pill

noun
  • Used other than figuratively or idiomatically: see bitter, pill. 

mischance

noun
  • Bad luck, misfortune. 

  • A mishap, an unlucky circumstance. 

verb
  • To undergo (a misfortune); to suffer (something unfortunate). 

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