The most common and most likely answer to this crossword clue is the 10 letter word UNDERWORLD
I've seen this crossword clue in The Daily Telegraph
U
N
D
E
R
W
O
R
L
D
More clues leading to the result UNDERWORLD
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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 UNDERWORLD mean?
UNDERWORLD noun- The world of the dead, located underneath the world of the living; the afterlife.
- That part of society that is engaged in crime or vice.
- The portion of a game that is set below ground.