manager vs second string

manager

noun
  • An administrator, for a singer or group. 

  • A person whose job is to manage something, such as a business, a restaurant, or a sports team. 

  • A window or application whose purpose is to give the user the control over some aspect of the system. 

  • The head coach. 

second string

adj
  • Not as good; of a lower quality or condition. 

noun
  • A unit of players which is considered to have a secondary level of talent and which usually plays after the first string. 

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