The most common and most likely answer to this crossword clue is the 7 letter word WASSAIL
I've seen this crossword clue in The Times
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More clues leading to the result WASSAIL
- Festive occasion used to be on part of boat
- Carol’s whiskey trouble
- On reflection, noticed son facing trouble in drinking bout
- Moan about idiot’s Christmas song
- Make painful sound about donkey in carol-singing
- Salute Carol
- Drink with mug
- Woman to go at holiday revelry
- Drink with Harry after work
- Seasonal drink was set out on a cruise
Buddy explains!

The straight part
We know that "Carol" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case carol = wassail.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 WASSAIL mean?
WASSAIL noun- A toast to health, usually on a festive occasion.
- The beverage served during a wassail, especially one made of ale or wine flavoured with spices, sugar, roasted apples, etc.
- Revelry.
- A festive or drinking song or glee.
- To toast, to drink to the health of another.
- To drink wassail.
- To go from house to house at Christmastime, singing carols.