The most common and most likely answer to this crossword clue is the 8 letter word FORESAIL
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result FORESAIL
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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 FORESAIL mean?
FORESAIL noun- (on a square-rigged ship) The lowest (and usually the largest) square sail hung on the foremast
- A square fore-and-aft sail set on the foremast, but behind it, on a schooner or other similar vessel.
- (on a sloop) A triangular sail set forward of the foremast: forestaysail.