house slipper vs slipperette

house slipper

noun
  • A slipper designed to be worn inside the house 

slipperette

noun
  • A soft slipper or similar foot covering, especially a disposable slipper of a kind distributed to train or aeroplane passengers. 

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