Defines the vocabulary of the first six centuries (600 - 1150 A.D.) of the English language, complementing the Middle English Dictionary (which covers the period 1100 - 1500 A.D.) and the Oxford English Dictionary (which documents the development of the English language to the present), the three together providing a full description of the vocabulary of English. Also see Dictionary of Old English Web Corpus which contains at least one copy of every surviving Old English text.