A Rapid Unplanned Disassembly, usually referred to as a RUD, is the current favorite term for a rocket or airplane coming apart very quickly, often in a ball of flame.
The term is currently having a surge of popularity, as it is Elon Musk's usual term for his rockets blowing up, crashing, or just tipping over -- which they have been doing a good bit of. (Not his fault, this is how we learn rocketry).
It's not a new coinage, by any means. 'RUD' has been around for a good long while; there are reports of it being used in the 1980s, and some suggestions that people are pretty certain they heard it used in the 60s... maybe. The concept certainly isn't new; since the 1930s we've had a multitude of terms for exactly these sorts of events, from kaputniks to hard starts to hard landings to catastrophic lithobraking to Uncontrolled Flight Into Terrain.