describing when one's head is so far up one's ass that one is wearing the ass as a hat. in other words, extreme stupidity.
A: Look at all those hurricane victims on their roofs, waving at the helicopters, begging for emergency food to be dropped down! Why don't they just leave?
B: You asshat.
A close cousin of the Ass-clown, typically identified by a jovial expression and an outward misunderstanding of how he/she is perceived, combined with a generally misguided conception of what is sociably acceptable amongst his/her fellow peers.
Said persons' frequent attempts at humor usually lead to he/she making an ass out of his/herself. Not to be confused with ass-hole.
"Quit throwing pennies at that homeless man, you asshat."