In the phrase "ugly Christmas sweater," the word "ugly" is a term of art, a description rather than a put-down. One wears an ugly Christmas sweater precisely because it is so over the top, crammed with images of weighted-down Christmas trees, cartoony reindeer, red-cheeked Santas, and leering snowmen. Sequins are encouraged, as are lights. And if the sweater is three-dimensional, all the better.

Though these sweaters have their roots in the relatively sedate Christmas cardigans and pullovers that were popular in the 1950s, in recent years the ugly Christmas sweater has become something of a cultural phenomenon. People parade their sweaters at ugly Christmas sweater parties. In some cities, these events have become so popular, they have been transformed into fundraisers for local charities, proving that even people with a taste for ironic humor understand the meaning of the holiday.