Associate; helper (4)
I believe the answer is:
ally
This clue is a double definition.
'associate' is the first definition.
(ally is a kind of associate)
'helper' is the second definition.
(I've seen this in another clue)
(Other definitions for ally that I've seen before include "One on one's side" , "Friend and colleague" , "Colleague, confederate" , "Crony" , "Comrade in arms" .)