entrust vs retain

entrust

verb
  • To trust to the care of. 

  • Can I entrust you with a secret? 

retain

verb
  • To keep in possession or use. 

  • To employ by paying a retainer. 

  • To hold back (a pupil) instead of allowing them to advance to the next class or year. 

  • To keep in one's pay or service. 

  • To hold secure. 

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