The most common and most likely answer to this crossword clue is the 5 letter word REEFS
I've seen this crossword clue in The Daily Telegraph
R
E
E
F
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 REEFS mean?
REEFS noun- A chain or range of rocks, sand, or coral lying at or near the surface of the water.
- A large vein of auriferous quartz; hence, any body of rock yielding valuable ore.
- A portion of a sail rolled and tied down to lessen the area exposed in a high wind.
- A reef knot.
- To take in part of a sail in order to adapt the size of the sail to the force of the wind.
- To pull or yank strongly, especially in relation to horse riding.
- (of paddles) To move the floats of a paddle wheel toward its center so that they will not dip so deeply.
- The itch; any eruptive skin disorder.
- Dandruff.