Heroin's moved close to the coast (7)
I believe the answer is:
inshore
'close to the coast' is the definition.
(inshore means near to the coast)
'heroin's moved' is the wordplay.
'moved' indicates anagramming the letters.
'heroins' anagrammed gives 'INSHORE'.
(Other definitions for inshore that I've seen before include "coming in to land" , "towards the coast from the sea" , "Close to the land" , "place near coast" , "not far from the coast" .)