Sugar syrup (8)
I believe the answer is:
molasses
'sugar syrup' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for molasses that I've seen before include "Dark syrup extracted from sugar cane" , "Thick dark treacle" , "Syrup drained from raw sugar for some lass" , "Syrup, by-product of refining" , "what refinement can bring" .)