Limb; MP (6)
I believe the answer is:
member
I believe this is a double definition.
'limb' is the first definition.
(I've seen this in another clue)
'mp' is the second definition.
(Member of Parliament)
(Other definitions for member that I've seen before include "One belongs to a group" , "either left or right wing, say" , "Projecting body part" , "Limb; society joiner" , "Part of the body - or of society group" .)