Fox is doing it wrong, it's actually Christmahanakwanzaka. (It's a all inclusive title for all the "Christmas time" holidays). I have always seen it as a joke though, people actually say it seriously? hmmm... what is the world coming to?
From what I understand, Christmakah originated from "The OC" when one of the characters wanted to celebrate the Holidays but not offend anyone. But maybe I'm clueless and it came in use a long time ago in an unrelated way.