nwn = no wipe needed
NWN occurs when you take a crap and you dont have to wipe.
FOr noobs: 'no wipe needed' means you take one wipe to make sure there is no residual you-kno-what left.
FOr pros: 'no wipe needed' means that you can tell if you need to wipe or not. You have developed a sort of 'spidy sense' for this.
"hey man, i just took a huge crap"
"really? was it nwn?"
"of course, smooth as silk"