disarticulate vs unclasp

disarticulate

verb
  • To disjoint. 

  • To amputate (a limb) at a joint without cutting the bone. 

unclasp

verb
  • to become unfastened 

  • to separate from being clasped 

  • to release the clasp from something 

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