The most common and most likely answer to this crossword clue is the 8 letter word BROODING
I've seen this crossword clue in The Daily Telegraph
B
R
O
O
D
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G
More clues leading to the result BROODING
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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 BROODING mean?
BROODING verb- To keep an egg warm to make it hatch.
- To protect (something that is gradually maturing); to foster.
- (typically with about or over) To dwell upon moodily and at length, mainly alone.
- To be bred.
- A spell of brooding; the time when someone broods.
- (of a bird) Broody; incubating eggs by sitting on them.
- Deeply or seriously thoughtful.