hireling vs scrubwoman

hireling

noun
  • An employee who is hired, often to perform unpleasant tasks with little independence. 

  • Someone who does a job purely for money, rather than out of interest in the work itself. 

  • A horse for hire. 

scrubwoman

noun
  • A woman employed to do general housework, such as cleaning a house or office. 

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