to wank,
to tame the one eyed monster,
to make the cyclops cry,
man's favourite outlet,
a date with mrs palm and her five
lovely daugters,
toss yourself off,
etc etc
"now on the subject of onanism...we dont want to find you hunched double on the sofa bedpumping your fist" (league of gentlemen)
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!"