Row is over little Susan (5)
I believe the answer is:
issue
'row' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'is over little susan' is the wordplay.
'over' is a charade indicator (letters next to each other).
'little susan' becomes 'sue' (I've seen this before).
'is'+'sue'='ISSUE'
Can you help me to learn more?
(Other definitions for issue that I've seen before include "Result, outcome; topic" , "Matter, point" , "Important problem" , "Subject, result, or publication" , "Continent" .)