Spiritualist (6)
'spiritualist' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for medium that I've seen before include "Average, mean" , "Spiritualist who conducts seances" , "Conduit of communication" , "Average; agency" , "Middle course for spiritualists" .)
'spiritualist' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for mystic that I've seen before include "Otherworldly" , "One who seeks spiritual union with God" , "Spiritualist" , "Of spiritual significance" , "Of hidden or symbolic meaning as in religion" .)