Discharge fellow into alcoholic drink (5)
I believe the answer is:
rheum
'discharge' is the definition.
(I've seen this before)
'fellow into alcoholic drink' is the wordplay.
'fellow' becomes 'he' (I've seen this in other clues).
'into' indicates putting letters inside.
'alcoholic drink' becomes 'rum' (alcoholic spirit).
'he' going within 'rum' is 'RHEUM'.
(Other definitions for rheum that I've seen before include "Discharge of water" , "Rhubarb genus; a head cold" , "Poetic tears" , "sign of illness" , "Watery fluid" .)