Rogue peed in vessel for disinfectant (5,3)
I believe the answer is:
sheep dip
'disinfectant' is the definition.
'rogue peed in vessel' is the wordplay.
'rogue' is an anagram indicator (letters go rogue).
'in' means one lot of letters goes inside another.
'vessel' becomes 'ship' (ship is a kind of vessel).
'peed' is an anagram of 'eepd'.
'eepd' inserted within 'ship' is 'SHEEP-DIP'.
'for' is the link.
(Other definitions for sheep dip that I've seen before include "Pesticide bath for proverbially silly animals" , "treatment of animals" , "in which a mite carried away?" .)