recruit vs second-stringer

recruit

noun
  • A supply of anything wasted or exhausted; a reinforcement. 

  • A hired worker 

  • A person enlisted for service in the army; a newly enlisted soldier. 

  • A new adult or breeding-age member of a certain population. 

verb
  • To enroll or enlist new members or potential employees on behalf of an employer, organization, sports team, the military, etc. 

  • To become an adult or breeding-age member of a population. 

  • To prompt a protein, leucocyte. etc. to intervene in a given region of the body. 

  • To supply with new men, as an army; to fill up or make up by enlistment; also, to muster 

second-stringer

noun
  • A person who is not good enough to be considered proficient but may be useful as a backup. 

  • A person who plays second string. A person who is kept on a sports team as a backup in case a "first-string" player is unavailable. 

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