The most common and most likely answer to this crossword clue is the 9 letter word SPINNAKER
I've seen this crossword clue in Independent
S
P
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N
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A
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R
More clues leading to the result SPINNAKER
- Tack into wind and run this sail
- A hook at the back splitting top sail
- Tack into wind, beginning to raise sail
- Regularly tack in top sail
- Wild prank in sea, not a feature of yachting?
- 27, perhaps, concealing a monarch’s sail
- Spirit blown over, filling topsail?
- Large sail secure in wind? Right
- Jack handles this type of bowler maintaining attack at both ends
- Small folded napkin put before the Queen. It is used before the main course
Buddy explains!

The straight part
We know that "It is used before the main course" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it is used before the main course = spinnaker.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 SPINNAKER mean?
SPINNAKER noun- A supplemental sail to the mainsail, especially a triangular one, used on yachts for running before the wind.