backstop vs barbed wire

backstop

noun
  • A wall or fence behind home plate. 

  • A catcher; the position of catcher. 

  • The player who stands immediately behind the striking base. 

  • Something serving to bolster or support a cover story etc. 

  • A thing or a person put in the rear or in the back of something to reinforce, hold, support. 

  • A default arrangement that holds if all else fails. 

verb
  • To bolster, support. 

  • To serve as backstop for. 

barbed wire

noun
  • Twisted strands of steel wire, often coated with zinc, having barbs evenly spaced along them; used to construct agricultural and military fences. 

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