acquiescence vs permission

acquiescence

noun
  • A silent or passive assent or submission, or a submission with apparent content, distinguished from avowed consent on the one hand, and on the other, from opposition or open discontent; quiet satisfaction. 

  • Inaction, passivity, or neglect to take legal action when it is called for in order to assert, preserve, or safeguard a right, and which inaction implies the abandonment of said right. 

permission

noun
  • authorisation; consent (especially formal consent from someone in authority) 

  • The act of permitting. 

  • Flags or access control lists pertaining to a file that dictate who can access it, and how. 

verb
  • To grant or obtain authorization for. 

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