Apocalypse
Etymology
From Greek “apokalypsis” (an uncovering, revelation), from “apo-” (off, away) plus “kalyptein” (to cover, conceal) — literally “an unveiling.” The Book of Revelation is titled “Apokalypsis,” so the word originally meant revelation, not catastrophe; the end-of-the-world sense came from what those visions described. That same “cover” root, meaning “well-covered,” also names the eucalyptus, whose flower buds wear a cap.
noun · /uh-POK-uh-lips/
A revelation or unveiling — and, in popular use, a catastrophic end of the world.
What it names
Disclosure of hidden truth, and how that original meaning got swallowed by the disaster it described.
Example
The leaked memo was a small apocalypse — not the end of anything, but a sudden unveiling of what management really thought.
Related idea
An epiphany is a personal, sudden insight; an apocalypse is, at root, a grand unveiling of hidden cosmic or ultimate truth — the disaster meaning is a later borrowing from the content of such revelations.