The most common and most likely answer to this crossword clue is the 7 letter word FLOTSAM
F
L
O
T
S
A
M
More clues leading to the result FLOTSAM
- Force to slam explosively causing wreckage
- Drifting wreckage seen as half of family lost at sea
- Force almost abandoned wreckage found at sea
- Wet rubbish? Female in the morning collects a great deal
- Ship's wreckage — beginning to find plenty in the morning
- Fish head almost blended, some pieces left on the surface
- Refuse female almost deliriously
- Leading frigate almost wrecked, debris seen
- Rubbish celebrity practically pocketing shedloads
- Rubbish celebrity almost pocketing loads
Buddy explains!

The straight part
We know that "wreckage found at sea" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wreckage found at sea = flotsam.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does FLOTSAM mean?
FLOTSAM noun- Debris floating in a river or sea, in particular fragments from a shipwreck.