Leg or arm (4)
I believe the answer is:
limb
This clue is a double definition.
'leg' is the first definition.
(I've seen this before)
'arm' is the second definition.
(I know that arm can be written as limb)
(Other definitions for limb that I've seen before include "Branch - member" , "Tentacle" , "A supporter" , "Jointed appendage" , "Branch - arm - leg" .)