enslave vs untie

enslave

verb
  • To make subservient; to strip one of freedom; enthrall. 

untie

verb
  • To free from fastening or from restraint; to let loose; to unbind. 

  • In the Perl programming language, to undo the process of tying, so that a variable uses default instead of custom functionality. 

  • To resolve; to unfold; to clear. 

  • To become untied or loosed. 

  • To loosen, as something interlaced or knotted; to disengage the parts of. 

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