look up any word, like porb:
 
1.
A life-altering, extremely messed up mistake, usually referred to in jest, but in actuality, quite serious.
Man, getting totally fucked up last night, jumping off a bridge, breaking every bone in my body and ensuring myself a life of paralysis was a mightily defunct blunderbus.
by Vocalsmoothie February 20, 2011
 
2.
A charabanc for bastards.
Agent 1: Look, here comes our ride.
Agent 2: Man, that's the blunderbus. Weren't your parents married?
Agent 1: Oops! My bad!
by TheNix November 05, 2010
 
3.
A blunder bus is where you masturbate. Taking a ride on the blunder bus is masturbating, and a bus movie is someone attractive that you think about while doing so.
That girl is real bus movie material, I gotta remember her for the blunder bus.
by Jesse January 12, 2006