Can Someone Help Me Find this Word?

[Rhondazvous]

Ye thanks. The word is geas. Now I have to think. The word appears to be Irish. So would it throw my readers off to have an African grisha lay a geas on someone?

Not at all.  There's a west african myth about a prosperous and handsome young man who could not, because of an agreement made by his mother with spirits to ensure his prosperity, eat fish - on pain of death.   Upon reaching manhood, his mother made many arrangements for the best of the local women to come and see which would be best suited to be his bride.  Most, he showed no particular interest in, but two were different.  He rebuked one outright and favored another, but both learned of his geas from his mother in preparation to be his wife.  The jilted prospective wife set out to poison him by crumbling fish into his stew...but the other had possession of a magical comb, which she drew through the stew, just in case, and removed all of the fish.  

-and they lived happily ever after, ofc.  

A good wife makes sure you don't eat shit that will kill you.

I like that story. Is it from Nigeria, the Ife tradition. I mistyped up above. It should say Orisa. Esu, Oya and Shango are prominent in this novel. But it's not an ex dous machine.