Something apocalyptic describes a catastrophic event that destroys or transforms the world as we know it, or warns of such an event. The word captures the sense of total devastation, the end of everything familiar.

Apocalyptic carries more weight than words like disastrous or catastrophic. A bad flood is a disaster. An apocalyptic flood reshapes the entire world. The word suggests not just destruction, but transformation so complete that nothing will ever be the same. When someone describes something as apocalyptic, they're emphasizing the scale and finality of the devastation, the sense that this is the end of an era or a way of life.