square off vs stand down

square off

verb
  • To get ready for a confrontation (debate, argument, fight). 

  • To increase the boxiness of (a design). 

stand down

verb
  • To wait; to stop pursuing, stop fighting, or relax from a heightened readiness posture. 

  • To withdraw or retire from a position or from a team. 

How often have the words square off and stand down occurred in a corpus of books? (source: Google Ngram Viewer )