The most common and most likely answer to this crossword clue is the 8 letter word SHALLOWS
I've seen this crossword clue in Financial Times
S
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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 SHALLOWS mean?
SHALLOWS noun- A shallow portion of an otherwise deep body of water.
- A fish, the rudd.
- A costermonger's barrow.
- To make or become less deep.
- An area in a large body of water with many shallow areas.