The term apocalyptic in its strict sense means “pertaining to an apocalypse,” a salient genre of the literature of the religious movement described below. Apocalypse means “revelation” in Greek and came to apply to the revelation of last things (eschatological events) to a seer, e.g., the apocalypse of John, commonly called the Revelation of John. We shall use the term “apocalyptic” in a wider sense, to designate a religious movement marked by an eschatological viewpoint found inter alia in the apocalypses.