Not in the current discharge (7)
I believe the answer is:
outflow
'discharge' is the definition.
(I know that outflow is a type of discharge)
'not in the current' is the wordplay.
'not in' becomes 'out' ('out' is the opposite to 'in').
'the current' becomes 'flow' ('flow' can be a synonym of 'current').
'out'+'flow'='OUTFLOW'
(Other definitions for outflow that I've seen before include "Amount of liquid moving away" , "Tofu owl (anag.)" , "Large amount transferred to another place" , "running away" , "Discharge" .)