backset vs flipside

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. 

flipside

noun
  • A necessary consequence or corollary of something that acts as a negation or counterbalance; especially one seen as opposite, or as pro versus con. 

  • The reverse, in contrast to the obverse. 

  • The B-side of a phonograph record. 

  • The occasion when we meet again (e.g. when I return from work, etc.; said on parting); later or tomorrow. 

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