Wreckage (6)
'wreckage' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for debris that I've seen before include "Rubble, heap of broken pieces" , "Broken remains" , "Refuse, litter" , "Remains - wreckage" , "Fragments of rubbish" .)
'wreckage' is the definition.
(flotsam is a kind of wreckage)
This is the entire clue.
(Other definitions for flotsam that I've seen before include "Rubbish on sea" , "Detritus" , "Goods lost" , "Wreck" , "Wreckage found floating" .)