1. Severe overheating of the core of a nuclear reactor resulting in the core melting and radiation escaping
   "The Chernobyl disaster was caused by a catastrophic nuclear meltdown";
   - nuclear meltdown
    
2. A disaster comparable to a nuclear meltdown
   "there is little likelihood of a meltdown comparable to the American banking collapse in March 1933"
    
3. [informal] A display of bad temper
   "he had a meltdown";
   - fit, tantrum, scene, conniption [N. Amer, informal], hissy fit [informal]

1. Reduce or cause to be reduced from a solid to a liquid state, usually by heating
   "melt down gold";
   - melt, run
    
2. [informal] Have an emotional breakdown or crisis
   "The child melted down when I said it was bedtime"

Derived forms: melting down, melts down, meltdowns, melted down, molten down

Type of: bad temper, break up, calamity, cataclysm, catastrophe, disaster, dissolve, ill temper, overheating, resolve, tragedy

Encyclopedia: Meltdown