dorsel vs sluggard

dorsel

noun
  • A pannier. 

sluggard

noun
  • A person slow to begin necessary work, a slothful person. 

  • A person who is lazy, stupid, or idle by habit. 

  • A fearful or cowardly person, a poltroon. 

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