backset vs drawing board

backset

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

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

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

drawing board

noun
  • The planning stage of a project. 

  • A plane surface or table to which paper can be fastened for drawing purposes. 

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