collision vs head-on

collision

noun
  • An instance of colliding. 

  • Any event in which two or more bodies exert forces on each other in a relatively short time. In a collision, physical contact of two bodies is not necessary. 

head-on

noun
  • A collision from the front. 

adv
  • With the front of a vehicle. 

  • With direct confrontation. 

adj
  • Of a collision, from the front or in the direction of motion. 

  • Direct, abrupt, blunt or unequivocal; not prevaricating. 

How often have the words collision and head-on occurred in a corpus of books? (source: Google Ngram Viewer )