drudge vs feudalism

drudge

noun
  • Someone who works for (and may be taken advantage of by) someone else. 

  • A person who works in a low servile job. 

verb
  • To labour in (or as in) a low servile job. 

feudalism

noun
  • A social system based on personal ownership of resources and personal fealty between a suzerain (lord) and a vassal (subject). Defining characteristics are direct ownership of resources, personal loyalty, and a hierarchical social structure reinforced by religion. 

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