Man with German backing (3)
I believe the answer is:
tim
'man' is the definition.
(short for Timothy)
'with german backing' is the wordplay.
'with german' becomes 'mit' ('with' in German).
'backing' shows that the letters should be reversed in order.
'mit' backwards is 'TIM'.
(Other definitions for tim that I've seen before include "Sir -- Rice, lyricist" , "Tiny ..., Bob Cratchit's son in A Christmas Carol" , "Tiny chap" , "Adjoin" , "Tiny Dickens boy from 'A Christmas Carol'" .)