Zamenhof Day or International Esperanto Day
Zamenhof Day or International Esperanto Day is held on December 15. International Esperanto Community. This event in the second decade of the month december is annual.
UN Arabic Language Day on December 18 (United Nations);
World Orgasm Day on December 21 (date for 2020. Celebrate the day of the winter solstice);
World Braille Day on January 4 (UN 1 November 2018 A/C.3/73/L.5/Rev.1)