bitter pill vs blocking

bitter pill

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

blocking

noun
  • The precise movement and positioning of actors in order to facilitate a performance (originally planned using miniature blocks). 

  • Blocks used to support (a building, etc.) temporarily. 

  • A feature that prevents a keyboard from registering multiple simultaneous keypresses that would cause ghosting. 

  • The act by which something is blocked; an obstruction. 

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