congest vs overcrowd

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. 

overcrowd

verb
  • To fill beyond reasonable limits, with people, animals, objects or information. 

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