abstention vs invasion

abstention

noun
  • Non-participation in the political world; as a country avoiding international affairs. 

  • The act of declining to vote on a particular issue. 

  • The act of abstaining or refraining (from). 

invasion

noun
  • A military action consisting of armed forces of one geopolitical entity entering territory controlled by another such entity, generally with the objective of conquering territory or altering the established government. 

  • The breaching of the skin barrier. 

  • The spread of cancer cells, bacteries and such to the organism. 

  • The entry without consent of an individual or group into an area where they are not wanted. 

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