Officer back with tea (6,4)
I believe the answer is:
second mate
'officer' is the definition.
(I have seen 'Naval officer' mean 'second mate' so perhaps 'officer' could also mean 'second mate')
'back with tea' is the wordplay.
'back' becomes 'second' (both can mean to support an idea or proposal).
'with' is a charade indicator (letters next to each other).
'tea' becomes 'mate' (South American hot drink).
'second'+'mate'='SECOND MATE'
(Other definitions for second mate that I've seen before include "Naval officer" , "Craftsman, perhaps" , "one involved in bigamy?" .)