Meeting of spiritualists (6)
I believe the answer is:
seance
'meeting of spiritualists' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for seance that I've seen before include "Medium experience?" , "Spiritualist meeting chaired by medium" , "Sitting - can see (anag)" , "Spiritualists meeting with medium" , "Sitting, session" .)