encounter vs take on

encounter

verb
  • To engage in conflict, as with an enemy. 

  • To execute someone extrajudicially. 

  • To meet (someone) or find (something), especially unexpectedly. 

  • To confront (someone or something) face to face. 

noun
  • A sexual encounter; sexual activity, especially unplanned or unexpected, between people not in a sexual relationship, that usually does not lead to the establishment of a relationship, and may or may not happen again. A sexual encounter could be consensual or non-consensual; in the latter case, it is a sexual assault. A consensual sexual encounter that happens only once is commonly known as a one-night stand. 

  • A hostile, often violent meeting; a confrontation, skirmish, or clash, as between combatants. 

  • A meeting, especially one that is unplanned or unexpected. 

  • A match between two opposing sides. 

  • An extrajudicial killing or execution. 

take on

verb
  • To attempt to fight, compete with, or engage with. 

  • To assume or take responsibility for. 

  • To (attempt to) dribble round (an opposition player). 

  • To catch on, do well; to become popular. 

  • To obtain the services of (a person) in exchange for remuneration; to give someone a job. 

  • To begin to have or exhibit. 

  • To acquire, bring in, or introduce. 

  • To grieve or be concerned (about something or someone). 

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