Objects thrown overboard (6)
I believe the answer is:
jetsam
'objects thrown overboard' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for jetsam that I've seen before include "Cargo cast overboard" , "lost cargo" , "that lands on shore" , "Cargo deliberately thrown overboard to lighten ship" , "Ship's discharge" .)