plodder vs skivvy

plodder

noun
  • One who plods. 

  • A person who works slowly, making a great effort with little result; a person who studies laboriously. 

skivvy

noun
  • A prostitute. 

  • A close-fitting, long-sleeved T-shirt with a rolled collar. 

verb
  • To perform menial work; to do chores, like a servant. 

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