apocalypseyoudaoicibaDictYouDict[apocalypse 词源字典]
apocalypse: [13] A ‘catastrophic event, such as the end of the world’ is a relatively recent, 20thcentury development in the meaning of apocalypse. Originally it was an alternative name for the book of the Bible known as the ‘Revelation of St. John the divine’, which describes a vision of the future granted to St John on the island of Patmos. And in fact, the underlying etymological meaning of apocalypse is literally ‘revelation’.

It comes, via Old French and ecclesiastical Latin, from Greek apokálupsis, a derivative of the verb apokalúptein ‘uncover, reveal’, which was formed from the prefix apo- ‘away, off’ and the verb kalúptein ‘cover’ (related to English conceal).
=> conceal[apocalypse etymology, apocalypse origin, 英语词源]
apocalypse (n.)youdaoicibaDictYouDict
late 14c., "revelation, disclosure," from Church Latin apocalypsis "revelation," from Greek apokalyptein "uncover, disclose, reveal," from apo- "from" (see apo-) + kalyptein "to cover, conceal" (see Calypso). The Christian end-of-the-world story is part of the revelation in John of Patmos' book "Apokalypsis" (a title rendered into English as "Apocalypse" c. 1230 and "Revelations" by Wyclif c. 1380).

Its general sense in Middle English was "insight, vision; hallucination;" meaning "a cataclysmic event" is modern. As agent nouns, apocalypst (1829), apocalypt (1834), and apocalyptist (1835) have been tried.