Pole of round German gold (3)
I believe the answer is:
rod
'pole' is the definition.
(I know that pole can be written as rod)
'round german gold' is the wordplay.
'round' is a reversal indicator.
'german' becomes 'd' (abbreviation for Deutschland ie Germany).
'gold' becomes 'or' ('or' is the heraldic name for gold).
'd'+'or'='dor'
'dor' back-to-front is 'ROD'.
'of' is the link.
(Other definitions for rod that I've seen before include "Spare it and spoil the child, they used to say" , "Stick - measure" , "Fishing pole" , "Cane used for flogging" , "Instrument of punishment" .)