Ocean debris (7)
I believe the answer is:
flotsam
'ocean debris' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for flotsam that I've seen before include "Things found floating from a ship" , "Wreckage adrift at sea" , "Things going adrift" , "The floating wreckage of a ship" , "Washed-up wreckage" .)