Does anyone know where avada kedavra came from? It is an ancient spell in Aramaic, and it is the original of abracadabra, which means 'let the thing be destroyed.' Originally, it was used to cure illness and the 'thing' was the illness, but I decided to make it the 'thing' as in the person standing in front of me. I take a lot of liberties with things like that. I twist them round and make them mine.