This article is about the religious meaning. For more uses of the word apocalypse, see Apocalypse (disambiguation).

Apocalypse (Greek: αποκαλυψις, disclosure), is a term applied to the disclosure to certain privileged persons of something hidden from the mass of humankind. The Greek root corresponds in the Septuagint to the Hebrew galah, to reveal. The last book of the New Testament bears in Greek the title Αποκαλυψις Ιωαννου, and is frequently referred to as the Apocalypse of John, but in the English Bible it appears as the Revelation of St John the Divine, or the Book of Revelation (of Jesus Christ, the Messiah). Earlier among the hellenistic Jews, the term was used of a number of writings which depicted in a prophetic and parabolic way, the end or future state of the world (e.g. Apocalypse of Baruch), the whole class is now commonly known as 'Apocalyptic literature'. However, the Apocalypse technically refers to the unveiling of God, in his guise as the Messiah, and not to all of the destruction of the world which will accompany God's Revelation of Himself to Humankind.

An Apocalypse in the terminology of early Jewish and Christian literature, is a revelation of hidden things given by God to a chosen prophet; this term is more often used to describe the written account of such a revelation. Apocalyptic literature is of considerable importance in the history of the Judeo-Christian-Islamic tradition, as beliefs such as the resurrection of the dead, judgment day, heaven and hell are all made explicit in it. Apocalyptic beliefs predate Christianity, appear in other religions, and have merged into contemporary secular society, especially through popular culture (see Apocalypticism). Apocalypse-like beliefs also occur in other religious systems; an example is the Hindu concept of pralay.