(n) A rank collection of dust, formed by years of dead skin, dried farts, and dandruff that collects on office chairs or anyplace else people put their gross asses.
Philly was doing his 'Ace Ventura' bit when he slammed his face onto an office chair. You should have seen the gigantic cloud of ass dust that exploded out of it.
by wilsonhenderson January 18, 2010
You can overdose on assdust, it can make you do all kinds of dumb shit like pay $10 for a glass of water.
by Joe-B-Wan December 24, 2010
The same as titty sprinkles...but for asses. The dust a fairy sprinkles on young girls asses around 13 or 14 years of age to enlarge the ass. Not to be mistaken with this so called "puberty".
by Tonkpils November 10, 2007