pierce vs unsnib

pierce

verb
  • To puncture; to break through. 

  • To penetrate; to affect deeply. 

  • To get to the heart or crux of (a matter). 

  • To create a hole in the skin for the purpose of inserting jewelry. 

  • to break or interrupt abruptly 

noun
  • A pierced earring. 

unsnib

verb
  • to undo, untie, or open or become undone, untied, or opened. 

  • Somehow she managed to unsnib the window and escape. 

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