a decorated paper tube that makes a noise when you pull it apart
Origin and usage
The noun cracker is formed from the verb crack and the suffix ‘-er’. It was first used in English in the early 16th century to refer to a liar or braggart, and later to a firework that made a loud noise. The Christmas-related meaning dates from the mid 19th century.
The noun cracker has a number of meanings, including a dry biscuit, a firework that explodes loudly, and something very good. In the meaning given above, a cracker was originally called a ‘cracker bon-bon’ and referred to a small parcel of sweets with a small explosive inside that caused it to make a noise when pulled sharply apart. Although the ‘bonbon’ part was soon lost and sweets replaced with more durable items, the general principle remains to this day: two people pull the tube apart, causing it to make a small bang, and the person who gets the larger portion keeps the contents. A modern cracker generally contains a paper hat in the shape of a crown, a printed joke or snippet of information, and some kind of small gift. While for many people crackers are an essential part of the festive meal, others have queried their continued use in light of the wastefulness of something that is bought simply to be discarded.
“Crackers!” said Dumbledore enthusiastically, offering the end of a large silver noisemaker to Snape, who took it reluctantly.
(J K Rowling, )
Christmas stocking, stocking-filler, Advent calendar