banshee
("woman of the fairies") supernatural being in Irish and other Celtic folklore whose mournful "keening," or wailing screaming or lamentation, at night was believed to foretell the death of a member of the family of the person who heard the spirit. In Ireland banshees were believed to warn only families of pure Irish descent. The Welsh counterpart, the gwrach y Rhibyn ("witch of Rhibyn"), visited only families of old Welsh stock
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