The most common and most likely answer to this crossword clue is the 5 letter word NOONE
N
O
O
N
E
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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 NOONE mean?
NOONE pronoun- Used in contrast to anyone, someone or everyone: not one person; nobody.
- The ninth hour of the day counted from sunrise; around three o'clock in the afternoon.
- Time of day when the sun is in its zenith; twelve o'clock in the day, midday.
- The corresponding time in the middle of the night; midnight.
- The highest point; culmination.
- The letter ن in the Arabic script.