Eg, arm or leg (4)
I believe the answer is:
limb
This clue is a double definition.
'eg arm' is the first definition.
(I know that arm is a type of limb)
'leg' is the second definition.
(I've seen this before)
(Other definitions for limb that I've seen before include "Part of body or branch of tree" , "Arm, leg or wing" , "Eg, arm, leg" , "Large tree branch" , "Tentacle" .)