The Ormulum or Orrmulum is a twelfth-century work of biblical exegesis, written by a monk named Orm (or Ormin) and consisting of just under 19,000 lines of early Middle English verse. Because of the unique phonetic orthography adopted by its author, the work preserves many details of English pronunciation existing at a time when the language was in flux after the Norman conquest of England. Consequently, it is invaluable to philologists and historical linguists in tracing the development of the language.