outflow in WordNet English dictionary

1. the process of flowing out
   outflow  effluence  efflux 
   
2. the discharge of a fluid from some container
   "they tried to stop the escape of gas from the damaged pipe"; "he had to clean up the leak"
   escape  leak  leakage  outflow 
   
3. a natural flow of ground water
   spring  fountain  outflow  outpouring  natural spring