Sandbank; counter (3)
I believe the answer is:
bar
I believe this clue is a double definition.
'sandbank' is the first definition.
(I know that sandbank can be written as bar)
'counter' is the second definition.
(bar is a kind of counter)
(Other definitions for bar that I've seen before include "Public house" , "Lawyers; pub" , "sovereign" , "Pub room; sandbank" , "Counter; prevent" .)