about-face vs turnabout

about-face

noun
  • A reversal in direction; a reversal of attitude or opinion. 

  • An abrupt turn to face the opposite direction. 

verb
  • To turn 180 degrees to face the opposite direction. 

  • To change opinion or attitude drastically. 

turnabout

noun
  • A reversal of a decision or opinion etc; a change of mind or flip-flop 

  • A merry-go-round. 

  • The act of turning about so as to face in the opposite direction 

How often have the words about-face and turnabout occurred in a corpus of books? (source: Google Ngram Viewer )