The weight gain that people tend to put on during the December Holiday season (Christmas, Hannukah, New Years, etc) due to eating and drinking more than usual. Especially prevalent in college/university students being home from the winter holidays, many of whom are likely spending an extended period of time away from the school gym.
Student 1: "Hey have you seen John? He's put on at least 10 pounds since we last saw him at the end of first semester!"
Student 2: "Looks like he put on a bit of a holiday gut."
by Anonymous6454 December 28, 2013
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