Sift and stir flour, sugar, baking powder, and nutmeg together in a bowl. Whisk eggnog, milk, egg, and oil together in a separate bowl. Pour eggnog mixture into flour mixture and stir until batter is moistened and slightly lumpy.
Heat a lightly oiled griddle over medium-high heat, about 350 degrees F (175 degrees C). Drop batter by large spoonfuls onto the griddle and cook until bubbles form and the edges are dry, 3 to 4 minutes. Flip and cook until browned on the other side, 2 to 3 minutes. Repeat with remaining batter.