Mexican standoff vs toss-up

Mexican standoff

noun
  • A stalemate, or a confrontation among two or more sides that no side can win. 

  • A near-collision between two trains; an averted cornfield meet. 

  • A pot that is split among the players because of a tie. 

  • An inconclusive standoff, ending in mutual retreat. 

  • A confrontation among two or more armed parties, none of which wants to attack first (fearing that the other could retaliate), but neither of which will disarm (for fear the other will attack). 

  • A three-way or more standoff. 

toss-up

noun
  • A decision in which neither choice is clearly favorable or unfavorable, or for which the outcome does not matter. 

  • Either of two outcomes that are equally likely. 

  • The toss of a coin used to decide some issue. 

How often have the words Mexican standoff and toss-up occurred in a corpus of books? (source: Google Ngram Viewer )