Soldiers on the German command (5)
I believe the answer is:
order
'command' is the definition.
(order is a kind of command)
'soldiers on the german' is the wordplay.
'soldiers' becomes 'or' (Other Rank).
'on' means one lot of letters go next to another.
'the german' becomes 'der' ('the' in German).
'or'+'der'='ORDER'
(Other definitions for order that I've seen before include "Direct or requisition" , "System" , "American helping" , "Rank" , "Instruction - arrangement" .)