APOCALYPSE, a designation under which the last book of the New Testament is frequently referred to. It is the title the book has in the Greek, 'Az-olcd.Xvtlits, which in the English version is rendered " Revelation." See REVELATION OF ST JOUN. The name is applied generally to predictions relating to the growth and triumphs of the Messiah's kingdom, especially as revealed in visions or expressed by means of symbols. The more important extra-biblical writings of this kind are noticed in the article which immediately follows.