Amateur member, person presiding (8)
I believe the answer is:
armchair
'amateur' is the definition.
(I've seen this before)
'member person presiding' is the wordplay.
'member' becomes 'arm' (member can mean a limb).
'person presiding' becomes 'chair' (a chair presides over a meeting).
'arm'+'chair'='ARMCHAIR'
(Other definitions for armchair that I've seen before include "Amateur" , "Comfortable seat for one" , "Comfortable seat with raised sides" , "Sort of detective" , "It's comfortable to sit in" .)