Calypso was the sea nymph in Homer's Odyssey who loved and detained Odysseus for seven years, and died of grief when she was forced to free him. Her name - which derives from the Greek kalyptein, to cover or conceal - literally means "hidden" or "I will conceal" in Greek.

Similarly, an apocalypse is an "uncovering" (from Greek apo, off, and kalyptein). And, as that which is uncovered is revealed, the Apocalypse of John of Patmos was renamed the Book of Revelation when Wycliff translated it into English in the 14th Century.