impact vs kick in

impact

verb
  • To collide or strike, the act of impinging. 

  • To stamp or impress onto something. 

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

  • 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. 

kick in

verb
  • To kick or strike so as to cause the object struck to collapse or fall inwards. 

  • To kick or strike (a person); to beat up 

  • To start, connect, or take effect, especially in a sudden way. 

  • To contribute, especially to a collection of money. 

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