overman vs overseer

overman

noun
  • A person who supervises others; a supervisor, especially in a mine. 

  • A person with great powers; a superman. 

verb
  • To provide with too many personnel; overstaff. 

overseer

noun
  • The manager of a plantation of slaves. 

  • An officer responsible for the care of the poor, making out lists of voters and those who had not paid taxes, etc. 

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