This is a topic of interest to me so I'm about halfway thru this video, where Mr Winkelman tries to pin down an accurate definition of shamans. He distinguises between Shamans, Clairvoyants, Mediums, Magicians, etc... I don't know if he's going off the deep end in the second half, but so far very interesting
Psychedelics and Culture, MOD3, What is Shamanism? - Interview with anthropologist Michael Winkelman
https://www.youtube.com/watch?v=uK4EMF2LtBI