the feeling you get after you take a shit where it seems like no matter how many times you wipe it feels like there are still poo particles around your ass.
"Man that was a messy shit. it gave me a badcase of cookie butt"
A person who's ass is so big, that it magically absorbs anything that you put in the crack, up to and including cookies, especially Keebler fudge stripe cookies. Anything put in the crack is never seen or heard from again.
or
A nickname for 1950's actor Stephen Zukowski. Also known as Num Nums Zukowski.
Hey, Num Num's ass crack is showing
Let's put a Keebler fudge stripe cookie in there.
Oh my God!! The adventures of cookie butt lives!!!!
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.