Preheat oven to 350°F. Butter and flour a 9x5-inch or 10-inch loaf pan. (Or spray with baking spray.) Set aside.
In a medium-size mixing bowl use a whisk to sift together flour, baking powder, baking soda, salt, nutmeg and cinnamon.
In a separate bowl whisk together eggnog, sugar, oil, vanilla and rum extracts with the eggs until fully combined. Add the wet ingredients to dry ingredients, mixing just until fully moistened.
Pour batter evenly into pan. Bake for 50-60 minutes until golden brown and a toothpick or cake tester inserted into the center comes back clean.
Cool in the pan for 20 minutes, then remove to a cooling rack to cool to room temperature.
Eggnog Glaze: In a small mixing bowl whisk together powdered sugar, vanilla extract and rum extract, nutmeg and enough eggnog to reach drizzle consistency. Drizzle slowly over bread, repeating until all of the glaze has been used. (It's fine if the bread is slightly warm.)
Store Eggnog Bread in an airtight container or wrapped in plastic wrap chilled in the refrigerator for up to 5-7 days.