The most common and most likely answer to this crossword clue is the 9 letter word EIDERDOWN
I've seen this crossword clue in Financial Times
E
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D
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R
D
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N
More clues leading to the result EIDERDOWN
- Bedcover has colour that is turning blue
- Part of bedding we’d ironed badly
- Denied row involved quilt
- Quilt we’d ironed badly
- I wondered about feathers
- I wondered about getting something to keep me warm
- . Said I had a blue quilt
- I wondered about 12
- Cover when one or other is caught not working?
- I wondered about what to discard on hot summer nights
Buddy explains!

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 EIDERDOWN mean?
EIDERDOWN noun- The down of the eider duck, used for stuffing pillows and quilts.
- A quilt stuffed with this down.