From Greek 'katastrophe' (an overturning) — originally the dramatic reversal in a Greek play, now any disaster.
An event causing great and often sudden damage or suffering; a disaster.
From Greek 'katastrophē' (καταστροφή, an overturning, a sudden turn, a dramatic reversal), from 'kata-' (κατά, down, against, completely) + 'strephein' (στρέφειν, to turn, to twist), from PIE *strebh- (to wind, to turn, to twist). In Greek drama, the 'katastrophē' was the dramatic reversal at the end of a play — the moment when the plot turns upside down and the resolution (whether happy or tragic) is reached. Aristotle used it as a technical term of dramatic structure. The sense of 'disaster' or 'calamity' developed from this theatrical meaning: a catastrophe is when everything turns over, when the world inverts
A 'catastrophe' was originally a plot twist, not a disaster. In Greek drama, it was the final turning point — the denouement where everything reverses. An 'apostrophe' (a turning-away) uses the same root: the punctuation mark shows where letters have 'turned away.' And a 'strophe' (a stanza) is literally a 'turning' — in Greek choral odes, the chorus physically turned as they sang each strophe. Even 'trophy' is from the same family: Greek 'tropaion' was a