Polish member enters spiritualist meeting, missing start (8)
I believe the answer is:
elegance
'polish' is the definition.
(I've seen this in another clue)
'member enters spiritualist meeting missing start' is the wordplay.
'member' becomes 'leg' (member can mean a limb).
'enters' means one lot of letters goes inside another.
'spiritualist meeting' becomes 'seance' (I've seen this before).
'missing start' means to remove the first letter.
'seance' with its first letter taken off is 'eance'.
'leg' inserted within 'eance' is 'ELEGANCE'.
(Other definitions for elegance that I've seen before include "Refinement in taste and dress" , "Fine quality" , "Showing good taste in dress or style" , "Refinement, polish" , "Graceful appearance or manner" .)