housemaid vs retainer

housemaid

noun
  • A female domestic worker attached to the non-servant quarter part of the house, as opposed to a scullery maid. 

  • A housewife. 

verb
  • To be a housemaid. 

  • To wait on someone hand on foot, to watch them. 

retainer

noun
  • A paid servant, especially one who has been employed for many years. 

  • A fee one pays to reserve the other's time for services. 

  • A device that holds teeth in position after orthodontic treatment. 

  • Any thing or person that retains. 

  • A dependent or follower of someone of rank. 

  • A retaining valve. 

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