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2.
crude definition:"brain fart"
Susan: "During my entrance-exam, I totally had a bad case of cranial flatulence"
by Krystra July 23, 2013
 
1.
When a person wants to make an excuse for his or her stupidity, but wants to make others laugh in the process, so as to take attention away from his or her own dumbass behavior. And, if you're apologizing for your own cranial flatulence (similar to a brain fart), and the person you're speaking to doesn't understand the terminology, you can (temporarily, at least) feel better about your own level of intelligence.
Dude: Wanna come drink with me this weekend?
Chick: Duh...I'm gonna be in New York!
Dude: Oh yeah...sorry...cranial flatulence!
Chick: What???
Dude: Never mind...you wouldn't understand (Secretly feels much better about himself).
by Pipsqueakier May 05, 2006