authority vs leg up

authority

noun
  • Status as a trustworthy source of information, reputation for mastery or expertise; or claim to such status or reputation. 

  • A reliable, definitive source of information on a subject. 

  • Persons, regarded collectively, who occupy official positions of power; police or law enforcement. 

  • Official permission; authorisation to act in some capacity on behalf of a ruling entity. 

  • A government-owned agency that runs a revenue-generating activity for public benefit. 

  • Power or right to make or enforce rules or give orders; or a position having such power or right. 

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 authority and leg up occurred in a corpus of books? (source: Google Ngram Viewer )