coven Look up coven at Dictionary.com
"a gathering of witches," 1660s, earlier (c.1500) a variant of covent, cuvent early forms of convent. Association with witches arose in Scotland, but not popularized until Sir Walter Scott used it in this sense in "Letters on Demonology and Witchcraft" (1830).
Ther vold meit bot sometymes a Coven .... Ther is threttein persones in ilk Coeven. [Crim. Trials Scot. III 606, 1662]