washbowl vs washtub

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. 

washtub

noun
  • A tub used for washing clothes. 

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