It depends what language you speak. For instance, in English, you would say "Merry Christmas", in French you would say "Joyeux Noël, and in Bulgarian, you would say "Весела Коледа". If you mean how do you say it in Antarctican, there is no official language of Antarctica, because there are no permanent residents of Antarctica, there are only scientists from different countries, stationed at bases around Antarctica.
France has a permanent research station in Antarctica called Dumont d'Urville. French is spoken at this station and by French researchers in the area. Additionally, French is one of the official languages of the Antarctic Treaty System, which governs the continent.
l'Antartique
Antarctica is not a lauguage
There are no countries in Antarctica. Informally, the standard language of science -- Antarctica is a continent dedicated to science -- is English. The second language of science is French.
Some say that Antarctica is the home of the wind.
Antarctica
You could say that Antarctica is on the southern side -- of earth, that is.
French is spoken on all continents, including some French speakers in Antarctica.
There is no native human life there.
Australia and Antarctica
ziptu'a