The gluteus maximus is the main extensor muscle of the hip. It is the largest and outermost of the three gluteal muscles and makes up a large part of the shape and appearance of each side of the hips.
Referring to the maximum amount of area a butt can take up. When the person gets more whale like the amount of area it takes up increases. Quite often when sitting down the butt takes on the characteristics of a couch.
That gluteus maximus doesn't fit through the door. Son that's not what your looking for. Look how much area it takes up.