departure vs invasion

departure

noun
  • A deviation from a plan or procedure. 

  • The act of departing or something that has departed. 

  • There are several significant departures, however, from current practice. 

  • The distance due east or west made by a ship in its course reckoned in plane sailing as the product of the distance sailed and the sine of the angle made by the course with the meridian. 

  • The difference in easting between the two ends of a line or curve. 

  • The desertion by a party to any pleading of the ground taken by him in his last antecedent pleading, and the adoption of another 

  • A death. 

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 departure and invasion occurred in a corpus of books? (source: Google Ngram Viewer )