congest vs unstop

congest

verb
  • To hinder or block the passage of something moving, for example a fluid, mixture, traffic, people, etc. (due to an excess of this or due to a partial or complete obstruction), resulting in overfilling or overcrowding. 

noun
  • A farmer whose lands do not support him adequately. 

unstop

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

  • To remove a stoppage; to clear a blockage. 

  • To unplug or uncork a container. 

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