The most common and most likely answer to this crossword clue is the 9 letter word NEVERMORE
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More clues leading to the result NEVERMORE
- Tyneside vicar backing humanist? Not again, not at any time!
- Navy constantly increasing, as 1 down’s 11 said
- Just about runs further – but not hereafter
- Message delivered by raven is not to be repeated
- Constant or fading corvine cry?
- Woman meeting Romeo or me, possibly all afternoon? Not even once again
- 21’s refrain is always the same – or less
- North-eastern state about to replace books – it won’t happen again
Buddy explains!

The straight part
We know that "21’s refrain" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case 21’s refrain = nevermore.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 NEVERMORE mean?
NEVERMORE adverb- Never again.