Question: what do you call a person who doesn't believe in santa claus?
Answer: How do you call a person who doesn't believe in Santa-Claus, Harry Potter nor the Flying Spaghetti Monster? I call them normal persons. Not asantaclausists, aharrypotterists, aflyingspaghettimonsterists, athorists, aanubisists, azeusists, nor atheists.