a sudden malfunction of a part or apparatus
"the right front tire had a blowout"
"as a result of the blowout we lost all the lights"
a gay festivity
"The annual Pride blowout downtown was packed with thousands of people celebrating all night long."
A sudden puncturing of a pneumatic tyre/tire.
"The loud bang from the blowout sent us scrambling to pull over safely on the highway shoulder."