The word was originally a late medieval Scots word (circa 1500) meaning a gathering of any kind, according to the Oxford English Dictionary. It derives from the Latin root word convenire meaning to come together or to gather, which also gave rise to the English word convene. The first recorded use of it being applied to witches comes much later, from 1662 in the witch-trial of Isobel Gowdie, which describes a coven of 13 members.
The word coven remained largely unused in English until 1921 when Margaret Murray promoted the idea, now much disputed, that all witches across Europe met in groups of thirteen which they called 'covens'.
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