backflip vs turnabout

backflip

noun
  • a total reversal in policy or opinion; a volte-face, a U-turn. 

  • An act of rotating one's body 360 degrees in the backward direction. 

verb
  • To perform a backflip (rotation of body). 

  • To completely reverse a policy or opinion; perform a U-turn. 

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 backflip and turnabout occurred in a corpus of books? (source: Google Ngram Viewer )