Dirge about bank (5)
I believe the answer is:
ridge
'bank' is the definition.
'dirge about' is the wordplay.
'about' indicates anagramming the letters.
'dirge' is an anagram of 'RIDGE'.
(Other definitions for ridge that I've seen before include "Narrow hilltop range" , "shelf" , "Top line of roof" , "Long, narrow range of hills" , "Brow" .)