For a work Christmas party, a festive yet professional outfit would be appropriate. Consider wearing a dress shirt or sweater with a Christmas tie or scarf, paired with dress pants or a skirt. Depending on the dress code, you could also wear a suit or dress. Add accessories like Christmas jewelry, such as a Santa hat or reindeer earrings, to add a bit of holiday spirit. Avoid wearing anything too flashy or revealing, as the focus should be on celebrating the season and your colleagues.