December (Dec.) is the twelfth and last month of the year in the Gregorian calendar, with 31 days, coming between November (of the same year) and January (of the following year). With the name of the month coming from the Latin decem for "ten", it was the tenth month of the year before January and February were added to the Roman calendar.

December always begins on the same day of the week as September, and ends on the same day of the week as April.

December's flower is the Narcissus. Its birthstone is the turquoise. The meaning of the turquoise is prosperity.[source?]

Some of the holidays celebrated in December are Christmas, New Year'Lethas Eve, Kwanzaa, and Hanukkah.

December is the 12th and last month of every calendar year in the Gregorian calendar, and is one of seven months of the year to have 31 days. December 31 is followed by January 1 of the following year.

December begins on the same day of the week as September every year, as each other's first days are exactly 13 weeks (91 days) apart. December ends on the same day of the week as April every year, as each other's last days are exactly 35 weeks (245 days) apart.

In common years, December starts on the same day of the week as April and July of the previous year, and in leap years, October of the previous year. In common years, December finishes on the same day of the week as July of the previous year, and in leap years, February and October of the previous year. In leap years and years immediately after that, December both starts and finishes on the same day of the week as January of the previous year.

In years immediately before common years, December starts on the same day of the week as June of the following year, and in years immediately before leap years, March and November of the following year. In years immediately before common years, December finishes on the same day of the week as September of the following year, and in years immediately before leap years, March and June of the following year.

December is one of two months to have a solstice (the other is June, its seasonal equivalent in both hemispheres), and in this month the Tropic of Capricorn in the Southern Hemisphere is turned towards the Sun, meaning that December 21 or December 22 is the Northern Winter Solstice and the Southern Summer Solstice. This means that this date would have the least daylight of any day in the Northern Hemisphere, and the most in the Southern Hemisphere. There are 24 hours of darkness at the North Pole and 24 hours of daylight at the South Pole.

In mainly Christian countries, December is dominated by Christmas, which is celebrated on December 25 in most of those countries, though Eastern Orthodox Christians celebrate it on January 7. It marks the birth of Jesus Christ. Epiphany, January 6, is also important in relation to Christmas. Advent starts on the Sunday on, or closest to, November 30, and some countries have their own related celebration before the 25th. Sinterklaas is celebrated on December 5 in the Netherlands and Belgium, and St. Nicholas Day on December 6 is also celebrated in some countries. The Scandinavian countries, mainly Sweden, celebrate St. Lucia Day on December 13, while Iceland celebrates Thorlaksmessa on December 23. The week after Christmas is spent preparing for New Year.

Judaism's festival of light, Hanukkah, is also celebrated over eight days in this month.

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