Apocalypse (ə-pŏk'ə-lĭps') n. [Middle English Apocalipse, from Late Latin Apocalypsis, from Greek apokalupsis, revelation, and apokaluptein, to uncover.] Anything viewed as a revelation, especially one that is highly significant for the person receiving it; a disclosure. Often used of a realization or revelation that changes a person's goals or style of life.