head-on vs resultant

head-on

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

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

adv
  • With the front of a vehicle. 

  • With direct confrontation. 

noun
  • A collision from the front. 

resultant

adj
  • following as a result or consequence of something; resulting. 

noun
  • a vector that is the vector sum of multiple vectors 

  • anything that results from something else; an outcome 

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