December is the 12th and last month of the year in the Gregorian calendar, and as such should properly be called dodecember. As the name suggests, December was originally the tenth month of the year, but government workers inserted additional months mid-year centuries ago, and no one ever bothered to rework the nomenclature.
December is:
Universal Human Rights Month
National Egg Nog Month
National Impaired Driving Prevention Month
National Fruit Cake Month
National Pear Month
No Gender December
December's flower is the Narcissus (preferably one of the verities that bloom in the winter)
December's children have the birthstone of Turquoise
The full moon in December is called Hunters' Moon or Ice Moon.