What is the X in X-mas?
(1957) A children's book by Dr. Seuss. The Grinch, a sour and unpleasant creature, tries to prevent the fun and merrymaking of Christmas in his village by stealing all the gifts and decorations. The villagers celebrate the holiday anyway, and the Grinch reforms.
Note: A miserly and unpleasant person — especially one who spoils other people's pleasures — can be called a “grinch.”