blockage vs leg up

blockage

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

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

  • The state or condition of being blocked. 

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

leg up

noun
  • A boost, a sudden improvement; an advantage, an edge. 

  • Assistance, help given to get started or overcome a problem or obstacle. 

  • The act of assisting another's progress over a wall or other obstacle by forming a step for one of their feet with one's hands. 

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