I fight a battle of a similar name to this everyday. Pants never seem to fit right.
But on a serious note this was a major German offensive launched December 16, 1944 toward the end of World War II.
It lasted a full month and its toll was felt hard on both sides. Close to 20,000 American soldiers were killed and the Germans saw nearly a fifth of their forces in battle go down.

Question:
Can you name the famous World War II battle launched on this day, 1944?