I was reading O'hara's 10 North Frederick and in describing a house he mentions a dumb-waiter, a speaking tube and a "busybody." What exactly is a busybody?
The "Philadelphia Busy Body" was common on houses 100-200 years ago. The series of mirrors allowed the lady of the house to see a street vendor coming down the street and stop him with his cart. If she didn't see the street vendor he would pass by her house and continue on. She might not get her fruits and vegetables for that day
A meddling or prying person
SYNONYMS: [informal] snoop, snooper, looky-loo, nosy parker
or a device for that purpose.