Outflow of currency (3)
I believe the answer is:
This clue could be a double definition.
'outflow' is the first definition.
(I have seen 'Tidal outflow ' mean 'ebb' so perhaps 'outflow' could also mean 'ebb')
'currency' is the second definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for ebb that I've seen before include "Outward flow of the tide" , "Not to wax" , "Type of tide" , "Go out or recede like tide" , "(Water) recede" .)