backset vs contretemps

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. 

contretemps

noun
  • An ill-timed pass. 

  • An unforeseen, inopportune, or embarrassing event. 

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