Strong-smelling dope hidden in boat (7)
I believe the answer is:
pungent
'strong-smelling' is the definition.
(thesaurus)
'dope hidden in boat' is the wordplay.
'dope' becomes 'gen' (I've seen this in other clues).
'hidden in' means one lot of letters goes inside another.
'boat' becomes 'punt' (I've seen this before).
'gen' put into 'punt' is 'PUNGENT'.
(Other definitions for pungent that I've seen before include "Strong-smelling" , "Sharp tasting/smelling" , "Acrid; sarcastic (humour)" , "Smelly" , "Incisive" .)