A fold of fat underneath the jaw line caused by an excess of body fat. Double chin.
"That fat muthafuckah has a humongous ass chin!"
by Tunmy AuGratin February 23, 2006
Having an indented or "cleft" chin that when you stare at carefully enough resembles the human ass.
I could swear Kevin had a piece of toilet paper stuck to his ass chin. Do you think he can really poop from it ?
by Steve the Kevin Hater October 27, 2007
Where you have a very deep cleft chin and it looks like a ass crack.
The advantage of an asschin is: you can blow your nose and wipe your ass at the same time>
by asshat January 22, 2003