A fork of Rural Dictionary
An Elf on the Shelf is an elf said to be sent by Santa, or from the North Pole, at least. They are said to watch kids be good during December, and report back to Santa if they're not. There are different kinds of elves, and they usually arrive between the day after Thanksgiving and the first week of December, while a kid is between six and eleven years old. They move overnight, often give gifts, and some are very mischievous. They sometimes come with Elf Pets, (either a dog or a reindeer) which stay all year but only move with elves.
"My Elf on the Shelf; Elfie moved into the kitchen last night!" said Clarissa.