This article studies what Anglo-Saxons in around 700--900 understood by the Latin plant-name elleborus, looking particularly at Aldhelm's Latin riddle Elleborus, which suggests that the word was understood to denote woody nightshade (Solanum dulcamara). It examines the semantics of Old English words that gloss elleborus in earlier Anglo-Saxon sources: wedeberge, ceasteræsc, ceasterwyrte, and ælfþone. The article finds evidence for the presence of a copy of Dioscorides’ De materia medica in seventh-century Canterbury. It also argues for a culturally significant connection between ingesting woody nightshade, the production of an altered state of mind attested in Latin as dementia cordis and in Old English as wedenheortnes, and elves. Ælfþone might originally have meant something along the lines of ‘vine which causes the symptoms which elves cause’. It seems likely that there was a custom of ingesting it deliberately to achieve mind-altering effects
