maisonette vs rooming house

maisonette

noun
  • an apartment often on two floors 

  • a small house 

rooming house

noun
  • A house which lets out furnished apartments. 

  • A building with small, basic, inexpensive apartments for rent, often without en-suite bathrooms. 

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