To completely blow it and endanger yourself and others in a dangerous situation. Downhill Skateboard Racing Legend Kevin Cooper was known for his notoriously dangerous antics on the racetrack and frequently "Cooped out", crashing out his fellow competitors.
"I'm feeling kind of sketchy, don't get too close to me. I feel like I might coop out."
A phrase used to describe rampage or spree of destruction. Referencing the famous "Killdozer Rampage" in which Marvin Heemeyer destroyed much of the town of Granby, Colorado on June 4th 2004 using his heavily modified bull dozer.
Dude, if the DMV doesn't stop fucking me around, I swear to god I'm going to end up pulling a granby.