maid vs scrubwoman

maid

noun
  • A female servant or cleaner (short for maidservant). 

  • A girl or an unmarried young woman; maiden. 

scrubwoman

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

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