When something explodes, typically unexpectedly. More for something that's air-inflated, but it could be a fireworks piece that first acted as a dud.
I kept pumping air into my new pool float, and all of a sudden, it went bladooey.

Driving down a back road, I ran over a sharp rock, and my front tire went bladooey.
by EBgigga August 24, 2009
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