toilet room vs washbowl

toilet room

noun
  • A room in which to use a toilet: a lavatory. 

  • A room in which to perform one's toilet, including dressing and grooming, particularly before execution. 

washbowl

noun
  • A sink in a bathroom, connected to a supply of water and a drain, in which one may wash one's face and hands. 

  • A basin for washing the face and hands; a washbasin. 

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