A person with too much flabby tissue of fat on the upper part of the back under the armpits causing the flesh to form rolls. Multiple rolls forming on top of each other depicts the classic 'backfat' look.
Plump, well-fed, obese nature often contributes to having backfat.
The symptom is often caused by over-indulging or a heavy diet of fried chicken, burgers, chips, fatty and sugary foods combined with lack of exercise.
On some occassions, backfat can be caused by the use of a bra that is too small, causing the flesh to be compressed until it appears like backfat. This is not a case or genuine backfat.
Backfatters are often seen in public, wearing tight clothing and displaying rolls of backfat.
Muffintops or rolls just above the hips also fall into the category of backfat although these are usually referred to more commonly as 'muffintop'.