No, something that has been microwaved cannot "grow back" after being removed from the object. Microwaving works by generating electromagnetic waves that excite water molecules and other polar molecules in the food, causing them to vibrate rapidly and generate heat. This heat is what cooks the food.
Once the molecules in the food have undergone this cooking process and any organic structures, such as cells or tissues, have been altered or damaged, they cannot revert to their original state. In other words, microwaving causes irreversible changes to the structure of the food.
Therefore, if a part of an object (e.g., food item) is removed after being microwaved, it will not regenerate or "grow back" in any way. It's crucial to handle microwaved food with care to avoid burns and to ensure it is cooked evenly and safely.