apparent vs head-on

apparent

adj
  • Clear or manifest to the understanding; plain; evident; obvious; known; palpable; indubitable. 

  • Capable of being seen, or easily seen; open to view; visible to the eye, eyely; within sight or view. 

  • Appearing to the eye or mind (distinguished from, but not necessarily opposed to, true or real); seeming. 

head-on

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

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

adv
  • With the front of a vehicle. 

  • With direct confrontation. 

noun
  • A collision from the front. 

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