backset vs comedown

backset

noun
  • A check; a relapse; a discouragement; a setback. 

  • Whatever is thrown back in its course, such as water. 

verb
  • To plow again in the fall; said of prairie land broken up in the spring. 

comedown

noun
  • A sudden drop to a lower status, condition or level; a disappointment or letdown. 

  • A calm, mellow period experienced after the initial high from taking drugs. 

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