The most common and most likely answer to this crossword clue is the 6 letter word UNMOWN
I've seen this crossword clue in Independent
U
N
M
O
W
N
More clues leading to the result UNMOWN
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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 UNMOWN mean?
UNMOWN adjective- Not mown; unmowed.