Rush, outpouring (5)
I believe the answer is:
spate
This clue is a double definition.
'rush' is the first definition.
(I know that rush can be written as spate)
'outpouring' is the second definition.
(I have seen 'Fast outpouring ' mean 'spate' so perhaps 'outpouring' could also mean 'spate')
(Other definitions for spate that I've seen before include "Sudden increased quantity" , "Sudden river flood" , "A sudden flood or rush" , "rash" , "Fast outpouring" .)