Plaintive note on current account (7)
I believe the answer is:
elegiac
'plaintive' is the definition.
(I've seen this in another clue)
'note on current account' is the wordplay.
'note' becomes 'e' (musical note).
'on' becomes 'leg' (cricket term, fielding positions).
'current' becomes 'I' (symbol for electric current).
'account' becomes 'ac' (abbreviation).
'e'+'leg'+'i'+'ac'='ELEGIAC'
(Other definitions for elegiac that I've seen before include "Wistful, mournful" , "Mournful like a sorrowful poem" , "Mournful, lamenting" , "Like classical couplets" , "Plaintive" .)