Christmas is sometimes referred to as X-Mas because the Greek letter "x" is the first letter of the Greek word for Christ, Xristos.
Christmas ketah taler kasurat X'mas, inggih punika panyingkatan sané adung sareng tradisi Kristen, krana aksara X ring basa Yunani punika singkatan saking Kristus utawi ring basa Yunani Chi-Rho.