1) Preposterously insane.
It can
mean something that is insane beyond someone's wildest imagination, to the point that it becomes contrary to reason or common sense.
2) Something that is really
hard to understand, which has to be repeated
twice, or thrice before one fully comprehends it. (It can't be over 7 times, otherwise it would be: Unununderstandable.)
3) Something that is unacceptable, and intolerable (esp. by whole societies, or religions.)
1: “Hey, Steve. Why is six afraid of
seven?”
“I
don't know,
Tim McGomnrey. WHY is six afraid of
seven?”
“Cuz 7 8 9. Haha..”
“HAHAHA... WAIT... THIS IS UNUNDERSTANDABLE!!”
*****************
2: “And this is why Americans like potatoes.”
“Professor, can you repeat that last part 3 more times?”
*The professor literally repeats it 3 more times*
“It's still ununderstandable, professor!”
“Get the &$@% out you little piece of #%£¥!!”
*****************
3: “I said I wanted a decaf! This is NOT a decaf! This is irregularly ununderstandable on so many levels, you are ALL fired!!”