countermeasure vs placebo

countermeasure

noun
  • Any action taken to counteract or correct another. 

  • Any of the devices and techniques used to impair the operational effectiveness of an enemy. 

placebo

noun
  • A dummy medicine containing no active ingredients; an inert treatment. 

  • The vespers sung in the office for the dead. 

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