when you go to take a number one and end up shitting instead; a wild ass ride.
Man I had a plop twist last night, I'm shook.
A Plop Twist is when you go to the toilet for a piss but get the sudden desire to take a shit.
Man 1: "Hey man, what took you so long? We were ready half an hour ago."
Man 2: "Sorry man, had a Plop Twist."