Entertainment / Literature / Geasa: (also spelled geisa or geis, plural geissi) A magical taboo or restriction placed on a hero in Old Irish literature. For example, Cuchulainn in the Tain is forbidden to eat the flesh of a dog because his own name means 'hound of Ulster.' (On a symbolic level then, eating a dog's meat would be an act of autocannibalism.) Such restrictions are almost archetypal--compare with Sampson and Delilah in biblical literature. Also compare with the tynged in Welsh literature.
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