The most common and most likely answer to this crossword clue is the 10 letter word NIGHTMARES
I've seen this crossword clue in The Daily Telegraph
N
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More clues leading to the result NIGHTMARES
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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 NIGHTMARES mean?
NIGHTMARES noun- A demon or monster, thought to plague people while they slept and cause a feeling of suffocation and terror during sleep.
- Sleep paralysis.
- A very bad or frightening dream.
- Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure.