This chapter examines some terminology and definitions of prophecy. It explores scholarly definitions from Classics, Ancient Philosophy, Jewish Studies, and early Christian studies before turning more specifically to Greek philosophical definitions, early Christian definitions, Origen’s own definitions, and scholars’ interpretations of Origen’s views on prophecy. It argues that while insights from various fields are relevant for understanding Origen, his definition of prophecy is highly unusual and focuses not just on future-telling, but revelation of mystic truths as well as understanding of time and the cosmos. The chapter concludes by demonstrating that previous scholarship on Origen’s view of prophecy has tended to limit itself to specific features rather than taking a wide-angled view of the topic as this book does.