when a girl wheres pants too high, so that the waist of the pants is over the bottom part of her stomach, to form an area between the vagina and stomach known as the vagumach. you can see this on many college girls who have already surpassed the muffin top, and who are now onto bigger and better things.
A door wall is a sliding-glass door or patio door. The term is yet another example of banal Michigan vernacular, where in the residents latch on to company names, trademark names, marketing terms and product names from local companies. The terms become embedded in the local vocabulary and eventually become accepted as actual valid words and phrases. In this case the term comes from Wallside Windows in Taylor, MI (a large window manufacturer), where 'door wall' is their created word for sliding-glass door.
"Bob! John's gonna bring over them doorwalls from Wallsides on Tuesdee afternoon 'round two-thirty. Get 'er done!"