blockage vs prevention

blockage

noun
  • The state or condition of being blocked. 

  • Synonym of constipation (“impairment of feces passage”). 

  • The thing that is the cause of such a state, blocking a passage. 

  • Synonym of thrombosis, synonym of thromboembolism, or synonym of embolism. 

prevention

noun
  • The act of preventing or hindering; obstruction of action, access, or approach; thwarting. 

  • precaution; forethought. 

  • Any measure intended to limit health-related risks (such as information campaigns, vaccination, early diagnosis etc.). 

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