barmaid vs carhop

barmaid

noun
  • A woman who serves in a bar. 

carhop

noun
  • A waiter or waitress who serves customers, especially in their vehicles, at a drive-in restaurant, sometimes on rollerskates. 

verb
  • To work as a carhop. 

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