Geas

In Gaeilge, a word for a restriction, proscription or binding, usually implicitly magical in nature. The word is sometimes mistranslated as "curse".

A geas is a requirement or set of requirements placed on a person, and implies that some form of wizardry has been invoked to make the requirement/s binding. For example, the great Northern Irish hero Cuchullain had a geas imposed on him requiring him never to refuse an offered meal. Sometimes geasa have a time limitation included, requiring a person to do something in such-and-such a time. Breaking or violating a geas always has bad results -- often the death of the person who bears the geas.

People can find themselves carrying multiple geasa, which can severely complicate their lives if the geasa conflict. Cuchullain, for example, also bore a geas requiring him not to eat dog meat...so that, when the Morrigan in one of her many disguises offered him a meal, and the meal turned out to be spit-roasted dog, the hero found himself caught in an impossible bind, one which was partly responsible for his death. (AWAB?)