loosen vs unstop

loosen

verb
  • To disengage (a device that restrains). 

  • To make loose. 

  • To free from restraint; to set at liberty. 

  • To become unfastened or undone. 

  • To relieve (the bowels) from constipation; to promote defecation. 

  • To become loose. 

unstop

verb
  • To unplug or uncork a container. 

  • To draw out the stops of (an organ). 

  • To remove a stoppage; to clear a blockage. 

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