EUCATASTROPHE

PRONUNCIATION: (yoo-kuh-TAS-truh-fee)

MEANING: noun: A happy ending, especially one in which, instead of an impending disaster, a sudden turn leads to a favorable resolution of the story.

ETYMOLOGY: Coined by J.R.R. Tolkien in a letter in 1944, from Greek eu- (good) + catastrophe, from kata- (down) + strophe (turning). Earliest documented use 1944.
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NEUCATASTROPHE - recent disaster in Berlin

EUCALASTROPHE - the koalas have no source of food any more

EU, CAT, ASK RO PHE - hey Felix, inquire in the row after Upsilon
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PS. Shouldn't the opposite of "catastrophe" be "anastrophe"? But that means something different. You want consistency? Don't look to language for it.