The cold moon is the first full moon in the month of December. The time of the Cold Moon is when the winter cold sets in and the nights become long and dark. This full moon is also known as the Long Night Moon.
The farmer's almanac included nicknames for the full moon depending on what month they occured. Most of these nicknames were based on the names North American aboriginal people used. Although many tribes gave nicknames to the full moon, the most well known come from the Algonquin tribes who lived in the area of New England and westward to Lake Superior.