about-face vs impact

about-face

verb
  • To change opinion or attitude drastically. 

  • To turn 180 degrees to face the opposite direction. 

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

  • An abrupt turn to face the opposite direction. 

impact

verb
  • To significantly or strongly influence or affect; to have an impact on. 

  • To stamp or impress onto something. 

  • To collide or strike, the act of impinging. 

  • To compress; to compact; to press into something or pack together. 

noun
  • A significant or strong influence or effect. 

  • A forced impinging. 

  • The striking of one body against another; collision. 

  • The force or energy of a collision of two objects. 

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