backset vs incompatible

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. 

incompatible

noun
  • A consequent of a contrary. 

  • An incompatible substance; one of a group of things that cannot be placed or used together because of a change of chemical composition or opposing medicinal qualities. 

adj
  • Of two things: that cannot coexist; not congruous because of differences; unable to function together due to dissimilarities. 

  • Incapable of being together without mutual reaction or decomposition, as certain medicines. 

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