backset vs tails

backset

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

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

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

tails

noun
  • Tailings; waste. 

  • The side of a coin that doesn't bear the picture of the head of state or similar. 

  • Tailings, feints. 

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