My husband has big lump on lower lip that is definately not a cold sore. Any idea what it may be. Last night he said it felt like he had bit his lip.?

Mucocele? He may have a mucocele, which is a mucous filled cyst that can occur on the inner mucosal surface of the mouth.
Traumatic swelling. Without looking at the bump, it is difficult to completely diagnosis the swelling. But if your husband stated that he had bit his lip, it's very possibly just a swelling from lip biting. If that's the case, then it would mostly likely go away in a couple of weeks. I would recommend an exam by your medical doctor or your dentist.
Mucocele? A common cause is a blocked minor saliva gland, which is a benign condition. A swollen area could certainly be from trauma. A long-standing lump could be a benign or cancerous growth. If it has not been there long, it's probably nothing serious, but get it checked out if it doesn't go away.