1. Literally, travel luggage that exceeds the dimensions of size or weight normally allowed on a plane or train, usually requiring a fee for it to be allowed onboard. My suitcase was only slightly over the weight limit, but the airline clerk still insisted on labeling my suitcase as excess baggage and slapping me with a fine.

2. Any person or thing that is unnecessary or unwanted and thus is or becomes burdensome. I know it's ungenerous, but Martin's younger brother has been nothing but excess baggage since we agreed to let him live with us.

3. A personal history, emotional disposition, or traumatic experience that is or becomes debilitating or burdensome in life. He carried the excess baggage of his abusive parents with him for years after leaving home. Her reclusiveness has become real excess baggage for her in recent months.