So the actual orgin of the word Shaman that has been cited is correct. According to anthropologists the practice for lack of a better word of a Shaman can be traced back to some of the earliest civilizations and found in most early cultures through out the world. This is using the same criteria of meaning for the word and involves more then just healing. While each culture does have slightly different practices they all meet the same basic criteria. Some people believe it was one of the earliest practices known to man but I have never found a actual article stating this.